Proceedings: Weeping Lovegrass Symposium

Transcription

Proceedings of the First
Weeping Lovegrass Symposium
(April 28-29, 1970)
R. L. Dalrymple, Symposium Coordinator and Proceedings Editor/Compiler
The Samuel Roberts Noble Foundation
Ardmore, Oklahoma
Table of Contents
Foreword
vii
Credits
ix
Symposium Report
x
Growth Patterns of Weeping Lovegrass and How They Relate to
Management: M. C. Shoop and E. H. McIlvain
1
Cytogenetics of Eragrostis: L. J. Streetman
10
New Varieties of Weeping Lovegrass through Plant Evaluation and Selection:
Paul W. Voigt
14
Weeping Lovegrass Establishment and Management of First Year Stands:
R. L. Dalrymple
21
Performance of Common Weeping Lovegrass in a Clipping Test:
R. P. Bates
28
Conservation Uses of Weeping Lovegrass (Eragrostis curvula):
Maurice Gamble
40
Burning Old Growth of Weeping Lovegrass: E. H. McIlvain and
M. C. Shoop
44
Research Results on Weeping Lovegrass Fertilization in North Central
Oklahoma: W. E. McMurphy and C. E. Denman
52
Fertilizing Weeping Lovegrass in Western Oklahoma: E. H. McIlvain
and M. C. Shoop
61
Weeping Lovegrass in Integrated Forage Systems: R. L. Dalrymple
71
Ermelo Lovegrass in the Renner Systems: Donald J. Dorsett
79
Grazing Studies on Weeping Lovegrass in North Central Oklahoma:
W. E. McMurphy
84
v
Nutritive Value and Grazing Comparison of Weeping Lovegrass and
Other Summer Grasses: R. L. Duble
90
What We Did to Get 495 Pounds of Beef per Acre from Weeping Lovegrass:
R. L. Dalrymple
101
Grazing Weeping Lovegrass for Profit—8 Keys: E. H. McIlvain and
M. C. Shoop
111
Over 200 Cow Units on 480 Acres of Weeping Lovegrass: Frank Tidwell
120
Winter Grazing of Weeping Lovegrass in Northwestern Oklahoma: M. C.
Shoop and E. H. McIlvain
124
Seed Production, Weeping Lovegrass Eragrostis curvula (Schrad.) Nees,
in Oklahoma: Robert M. Ahring
133
An Example of Weeping Lovegrass in a Diversified Farming Program:
Bob Drake
141
Effects of Fertilizer and Clipping Frequency on Weeping Lovegrass:
Jerold Lee Rogers
147
Weeping Lovegrass for Vegetating Strip-Mine Spoils in Appalachia:
Willis G. Vogel
153
Weeping Lovegrass Evaluations: Arnold G. Davis and Jacob C. Garrison
162
vi
Foreword
Weeping lovegrass originated in Africa and was introduced into the United States
during the mid-1930s. It was a very successful grass, readily vegetating the naked,
erodable, wind-blown soils of Oklahoma, Texas, and other areas, and providing high
levels of forage production for livestock. Weeping lovegrass has always been an excellent soil conservation grass in independent private producer use as well as one of the
components of the United States Department of Agriculture’s Soil Bank programs of the
1950s and the Crop Reserve Program of the 1980s and ’90s. The grass has been used
extensively in highway and other revegetation areas. Without a doubt, weeping lovegrass
helped greatly to arrest wind erosion on fragile sandy soils during the droughts of the
1950s, 1970s, 1980s, and 1990s, and provided much livestock forage at the same time. It
is an old introduced grass that will continue to work into the next millennium.
Weeping lovegrass is used as an important forage in South Africa, Argentina, and
the United States. Various agencies and institutions, including the Noble Foundation,
have researched and demonstrated its forage value from the 1940s to the present. Much
initial forage research work and its practical application were accumulated in the 1950s
and 1960s. Agricultural Division personnel at the Noble Foundation organized and
presented the “First Weeping Lovegrass Symposium,” which was held on April 28-29,
1970. The purpose was to present to the producer public, consultants, and researchers
accumulated pertinent weeping lovegrass forage management information so that any
manager could better manage the resource. A published proceedings was available at the
symposium. Coinciding with the symposium was the Noble Foundation’s release of a
new bulletin on weeping lovegrass management. The symposium, its published proceedings, and the bulletin Weeping Lovegrass Management all received great local, regional,
vii
national, and international recognition and use. These functions and publications led to
renewed extensive research in South Africa on weeping lovegrass; the bulletin was
translated to Argentine Spanish by the Argentineans and distributed there, and it received
considerable circulation in South Africa.
The original “First Weeping Lovegrass Symposium” turned out to be the only
such meeting, known to us, in the world in the twentieth century. Grass management
information never goes out of date. The original proceedings of the symposium is being
reprinted in 2000 for the producers, the real people we work for, consultants, and educators, and out of respect to the seventeen presenters from ten organizations or farms and
ranches. The soil, forage, and stock management information in the proceedings is as
relevant in 2000 as it was in 1970. Economics data merely need to be updated by the
reader. Sit back, read, and enjoy!
R. L. Dalrymple
Forage Management Agronomist
viii
Credits
The success of the symposium was the result of many people working together.
A special “thank you” is due them.
The publicity release sources
The session chairmen−Roy A. Chessmore, Kerr Foundation, Poteau, Oklahoma;
Billy Tucker, Oklahoma State University, Stillwater, Oklahoma; Gary D.
Simmons, Noble Foundation, Ardmore, Oklahoma; Joe Cole, Texas Agricultural
Extension Service, Denton, Texas; and Jim Whitworth, Soil Conservation Service,
Fairview, Oklahoma
The door prize donors−Ardmore Chamber of Commerce, Comet Feed Mills,
Wilkinson Feed & Seed Store, and The Samuel Roberts Noble Foundation, all of
Ardmore, Oklahoma
Weeping Lovegrass Symposium Program Committee
Symposium Coordinator and Proceedings Editor/Compiler
R. L. Dalrymple, Forage Management Agronomist
Agricultural Division
Noble Foundation
Ardmore, Oklahoma
E. H. McIlvain, Research Agronomist−Member
Southern Great Plains Field Station
Woodward, Oklahoma
Wilfred McMurphy, Assistant Professor−Member
Agronomy Department
Oklahoma State University
Stillwater, Oklahoma
Thanks also to their many helpful colleagues.
ix
Symposium Report
A total of 245 registered and “detectable” attendants were at the weeping
lovegrass symposium. Farmers and ranchers represented thirty-seven percent of this
attendance, while seventeen percent and sixteen percent were from private organizations
and the Soil Conservation Service, respectively. Personnel from Bureau of Indian Affairs, Agricultural Extension Services, Agricultural Stabilization & Conservation Service,
Farmers Home Administration, and agricultural research personnel made up the remaining thirty percent of the attendants. Their respective percentages ranged from three to
eight percent.
About fifty percent of those attending indicated where they first heard of the
meeting. Sixty percent of these listed Noble Foundation as their first contact, twenty
percent listed magazines, newspapers, television-radio, and twenty percent listed agricultural agencies or person to person contact. About 2000 individual mailouts were made to
individuals and numerous organizations. Noble Foundation consultees made up thirteen
percent of the attendance.
Attendants were from all regions of Oklahoma. Texans were primarily from
central and northern Texas. There were representatives from Kansas, Missouri, and
Arkansas. Twenty percent were from outside of Oklahoma and, of those, all but two
percent were Texans. People from the perimeter of the attendance area were from
Hutchison, Kansas; Columbia, Missouri; Little Rock and Batesville, Arkansas; and
Amarillo, Abilene, Rising Star, Temple, and Henderson, Texas.
The percentages of attendants from various ranges in distance from Ardmore,
Oklahoma, are given in the following table. Eighty-six percent were from distances
greater than twenty-five miles from Ardmore; seventy-one percent from greater than fifty
miles, forty-two percent from greater than 100 miles, and six percent from greater than
200 miles.
% Attendants from Various Distances from Ardmore, Oklahoma
Miles from Ardmore
Ardmore
Ardmore to 25 miles
25 to 50 miles
50 to 75 miles
75 to 100 miles
100 to 125 miles
%
6.4
7.8
15.1
10.5
18.3
9.1
Miles from Ardmore
125 to 150 miles
150 to 175 miles
175 to 200 miles
200 to 250 miles
250 to 300 miles
Over 300 miles
x
%
12.8
8.7
5.9
2.3
1.8
1.4
Growth Patterns of Weeping Lovegrass and
How They Relate to Management1
M. C. Shoop and E. H. McIlvain
Range Scientist and Agronomist
U.S. Southern Great Plains Field Station
Woodward, Oklahoma
Introduction
We, both growers and scientists, need to understand how weeping lovegrass
(Eragrostis curvula) grows so that we can manipulate it to our advantage. By applying
the knowledge of how weeping lovegrass (lovegrass) grows, growers can solve the
problems peculiar to their own situations. Scientists can use the knowledge to develop
new management practices and to interpret the results of treatment and other influences.
Raymond (1964) states an important principle: “. . . each cut is both a harvest
itself and a treatment for the next harvest . . .”
Research with lovegrass has been in progress at Woodward for over thirty years.
However, only recently have we recognized its outstanding potential for intensively
managed, high-producing pasture. Previously we studied it as a range grass—which,
however, it is not.
Much of the following discussion of lovegrass is based on the Woodward area,
and specifics must be tempered with due consideration of the fact that there will be some
variation, due to local climates and soils. Times or rates of development also vary with
growing conditions. Also, the studies are still in progress, and a few of the findings may
be modified when more data become available.
Description of Weeping Lovegrass
Weeping lovegrass is a vigorous-growing perennial with an extensive root system.
It is a bunch grass with numerous tillers (shoots), and isolated plants have crowns up to
15 inches in diameter. Only a small percentage of shoots produce seedstalks.
Lovegrass leaves are long (18 to 36 inches) and narrow, and curve downward to
give the grass a characteristic “weeping” appearance. The smooth leaves taper to a fine
point. The sheaths at the base of the leaves are purplish red.
1. A progress report of cooperative investigations of the Crops Research Division, Agricultural Research
Service, U.S. Department of Agriculture, and the Oklahoma Agricultural Experiment Station, Stillwater,
Oklahoma.
1
The seedhead of weeping lovegrass is an open panicle (shaped like that of oats)
which is 6 to 12 inches long and “lacey” in appearance. Plants in bloom have a distinctive
sweet odor. Seedstalks are often 3 to 4 feet high. A pound of seed contains about 11/2
million seeds.
Ecology
In its native habitat in central Africa, lovegrass is considered an important pioneer
grass that occupies land before the taller, longer-lived grasses take over (Bews, 1929). In
the United States, lovegrass grows well in Oklahoma and in the states south and east of it,
in the foothill areas of Arizona and New Mexico, and along the Atlantic Coast. It grows
best on soils that yield their moisture readily, as sandy soils, but it grows well on a wide
variety of soils.
Development of Seedlings
Lovegrass seedlings start emerging from a 1/4-inch depth four to five days after
planting, if moisture and temperature are adequate.
For about the first three weeks after emergence, a seedling has only a “thread of
life” for a root system. This is the seed root, which usually consists of a single strand with
only a few minor branchlets.
The permanent crown roots start growth at about three weeks, and the seed root
disappears by about the eighth week (Scott and Rabie, 1956). Until the crown roots are
well established, the seedling is highly susceptible to disturbances such as animal trampling or vehicle travel.
Growth is slow during the first several weeks. However, after the crown roots are
established, the seedlings grow much faster and form their first new shoots during about
the fourth to sixth week (Leigh, 1960; and Scott and Rabie, 1956).
During the first year, the seedlings reach varying degrees of maturity, depending
upon growing conditions. Under highly favorable conditions, lovegrass will flower and
set seed the first year, but under less favorable conditions, it will not flower until the
second year.
Development of Mature Plants
Season of growth: Lovegrass plants at Woodward start some growth in March and
April when the weather warms up. However, growth is slow until late April. At least part
of the new growth in spring is merely a continuation of growth of leaves and shoots that
grew the previous summer.
2
Lovegrass remains green until it receives a hard freeze. It continues to grow much
later in the fall than most warm-season grasses. Some green growth may continue all
winter in the protection of tall leafage, but not usually in closely grazed or mowed grass.
Growing point: The growing point (apical meristem) of lovegrass remains close to
the surface of the soil until the initiation of the flowering stem. (The growing point
produces all the leaves and the seedhead of a shoot.) The growing points may be below
the soil surface or may be slightly above if they are located on shoots derived from buds
located higher on a parent shoot. Thus, the growing points are well protected from normal
grazing and mowing. However, extremely close mowing or grazing can cut off some
growing points, especially if plants are growing on hummocks.
Removal of the growing point of a shoot causes it to stop production of new
leaves and causes its death as soon as those leaves already produced have matured. Killed
shoots must be replaced by the development of new shoots from buds—and this requires
time.
Leaves: All leaves grow from near the soil surface (basal) until the seedstalk
(culm) starts to grow. Then the last four leaves are elevated on the stem. As with other
grasses, the leaves arise successively above the last previous leaf and on the opposite side
of the shoot. Thus, half of the leaves are on each side of the shoot.
The first leaves at the base are the shortest. Successive leaves are progressively
longer until near the top where they become shorter again.
Leaves are divided into two parts. The first part that appears is the blade, and the
second is the sheath (base). The blade and sheath are separated by a distinct area (the
collar) that is yellowish on growing leaves and has a tuft of short hairs on the inner
surface.
Both the blade and sheath grow only from growth areas located at their bases;
consequently, the tops are the oldest. Thus, when the tip of a leaf is cut off, it will continue to grow until the basal areas mature.
Lovegrass shoots that have seedheads normally produce about twelve leaves.
Close examination may reveal that some of the oldest, smallest leaves have disappeared
from the base of the shoot. The number of leaves can be used to determine the maturity of
shoots during the vegetative phase. After the seedstalk is in the boot, the development of
the stalk reveals maturity.
Seedstalks: Only a small fraction of the shoots of a lovegrass plant normally
produces seedstalks at any one time. Nitrogen fertilization and good growing conditions
increase the proportion of shoots that produce seedstalks.
History of shoots: Under good growing conditions at Woodward, lovegrass matures seed in about six to eight weeks. A typical pattern of growth for the first crop under
good conditions is approximately as follows:
3
Date
April 1
May 1
May 20
May 30
June 5
June 10
June 15
Observed growth
Some green growth
Leaves six inches long
Stems emerging from crown (in boot)
Seedheads emerging from boot
Flowers blooming at tip
Seed ripe at tip
Seed shedding at tip
Growth rate: The longer a shoot grows, until it approaches maturity, the greater is
its rate of growth (Fig. 1). For example, during the first week of initial growth in May, or
of regrowth later in the summer, the daily production of forage on a pasture may be only
about 10 pounds per acre, but a few weeks later it may be 100 pounds per acre.
3000 -
2500 -
Forage yield, lb/acre
2000 Fertilized
1500 -
1000 -
500 Unfertilized
0Apr
15
Apr
29
May
8
May
14
May
21
May
27
June
3
June
11
Fig. 1. Forage yield of weeping lovegrass at various dates (growth curve) based on preliminary data
4
The growth-rate pattern is an extremely important consideration in management for
high forage production. It is obvious that yearlong production of forage is going to be much
less, if lovegrass is grazed frequently or continuously, than if it is let to grow until it is about
six weeks of age. The principle here is that shoots with more leafage, such as those have
that are let to grow the longest between grazings, produce more food to produce faster
growth. Each lovegrass shoot can be likened to a factory—the larger the factory, the greater
is the total production.
Newly cut-off leaves can make up to two inches of growth in a day. Rate of regrowth is increased by nitrogen fertilization and, of course, is fastest under the best growing
conditions.
Shoot (vegetative) buds: Immediately above the point at which each basal leaf joins
the main “trunk” of a lovegrass shoot is a bud which may develop into a new shoot. Since
each shoot has many basal leaves and there are many shoots per plant, each lovegrass plant
has a large potential for developing new shoots.
Healthy plants produce more new shoots than unhealthy ones. Also, plants fertilized
with nitrogen produce many more new shoots than unfertilized plants.
Plant units: A clump of lovegrass may be one or many plants, depending on the
source of the shoots or if previous connections with other shoots have broken. Apparently,
materials are exchanged between shoots that are attached as a unit, a stool (Leigh, 1960).
However, the significance of this is not known.
Root source and distribution: The roots of lovegrass are extensive vertically and
horizontally. On sandy soils, healthy lovegrass commonly has roots down 10 to 15 feet.
Horizontal roots can reach out at least 3 feet and fill all of the soil surface between
plants. They make lovegrass very effective in using light rain showers and in preventing
other plants from establishing.
Root growth: The roots from the crowns grow rapidly and extend the root system.
These roots are large in diameter and may be thought of as first-order roots. Each first-order
root from the crown branches into a relatively few second-order roots that are smaller.
These in turn branch into a few even smaller third-order roots.
New roots are very white and semitranslucent. However, as they age, they turn buff
colored.
All new roots have microscopic-size root hairs near their tips. The root hairs disappear as the areas behind the tips mature.
Root tip: The growing point (tip) of roots that stopped growth during 1969 usually
did not resume growth. Instead, they branched behind the tip or were replaced by new roots.
5
Physiology in Relation to Management
Spring Injury: Our studies show that early spring cutting or grazing of lovegrass
before it is about 6 inches tall significantly reduces summer forage production. Studies of
the effect of spring cutting are continuing.
Heavy freezes in late April and early May can kill new leaves and shoots or even
whole plants. Loss of stands in swales is sometimes due to a late freeze.
Winter injury: Studies at Woodward show that up to 60 percent of lovegrass
stands were winterkilled by mowing or grazing in September, October, or November.
During two years, the kill was most severe in September. However, it was most severe in
October of one year, and November of another year.
Crider (1945) also found that fall mowing could cause winter loss of a stand. The
reason fall mowing causes winterkill is not known. Until additional study shows under
what conditions, if any, lovegrass can be cut in the fall, all mowing and grazing should be
avoided from about six weeks preceding the average date of first frost until a hard freeze
has turned lovegrass straw-colored. In northwestern Oklahoma, lovegrass should not be
grazed or mowed in September, October, and November. The forage produced during fall
should be saved for excellent winter grazing.
Spot grazing: Since leaves usually grow 1 to 2 inches per day after being cut off, a
grazed shoot is regrazeable in one to three days. This regrowth is the most palatable grass
in the pasture and will be regrazed.
A long period of grazing causes some plants in the pasture to be repeatedly
grazed. Whenever a shoot is grazed or mowed so that little or no green leaves are left, it
is forced to draw upon its stored food to grow new leaves. Continued frequent use of
stored food can cause the plant to starve to death. This is the cause of most spot die-out in
continuously grazed pastures.
Drought and nitrogen: Lovegrass will continue to grow until virtually all the
available moisture is extracted from the soil. This is especially true when it is fertilized
with nitrogen (N).
Highly fertilized lovegrass (over 30 pounds of N per acre per application at
Woodward) that is allowed to grow undisturbed has a great amount of transpiring foliage
and is killed by less severe drought than is grazed or mowed grass, or unfertilized grass.
Grazing or mowing at six-week intervals reduces transpiration and drought kill as compared with less frequent use. Drought losses of fertilized lovegrass are most frequent and
extensive on the heavier textured and more droughty soils.
To prevent drought injury of fertilized lovegrass, N should be applied only at light
rates (about 30 pounds of N per acre), and only as often as it appears that the grass has
used up most of the last application, as judged by production and color of foliage. A crop
6
of lovegrass at Woodward will use up 30 pounds of N per acre during forty days of
growth when rainfall is average.
Effect of cutting on foliage: In general, the more frequently (or the younger)
lovegrass is cut or grazed, the lower the total production of forage during the growing
year (Denman, Elder, and Heller, 1953; and Steinke and Booysen, 1968). Furthermore,
the forage yield of the next crop is less on the most frequently cut lovegrass.
However, as with other grasses, forage quality and palatability drop as the grass
approaches maturity. Consequently, a balance must be struck between production and
forage quality. Preliminary data indicate that the proper balance is obtained on dryland
pastures at Woodward by grazing or cutting at about six-week intervals.
Effect of cutting on roots: Clipping lovegrass has been found to reduce the growth
of its roots (Crider, 1945; Scott, 1956; and Steinke and Booysen, 1968). One close clipping at 1 to 2 inches was found to completely stop root elongation for sixteen days
(Crider, 1945). The period of stoppage was found to be greater with each successive
cutting (Scott, 1956). However, cutting lovegrass at a 4-inch stubble height, rather than 1
or 2 inches, greatly reduced the effect of clipping on root growth (Scott, 1956). Under
some conditions, new roots may grow from the crown following cutting (Crider, 1945;
and Scott, 1956).
Effect of clipping on food reserves: The carbohydrate food reserves in the roots
and crowns of lovegrass are reduced in concentration and total quantity by frequent
cutting (Steinke and Booysen, 1968). This could be important if the carbohydrate reserves are reduced sufficiently by frequent close grazing that regrowth is slowed, or the
plants do not have enough reserves left to resume growth in the spring. Steinke and
Booysen (1968) found that the crown of lovegrass was far more important than the roots
in storage of carbohydrates.
Palatability: Lovegrass fertilized with N is much more palatable to cattle than is
unfertilized grass. The fertilized grass is considerably more succulent. Denman, Elder,
and Heller (1953) report that fertilized lovegrass contained as much as 26 percent more
moisture than did unfertilized.
Leigh (1960 and 1961) associated low palatability of some strains of lovegrass
with a low content of phosphorus or potassium. However, our preliminary results did not
indicate that phosphorus fertilization improved palatability of common or ‘Morpa’
lovegrass.
7
Literature Cited
Bews, J. W. 1929. The world’s grasses; their differentiation, distribution, economics and
ecology. Longmans, Green and Co. London, N. Y. p. 163, 480 p.
Crider, Franklin J. 1945. Three introduced lovegrasses for soil conservation. U.S. Dept.
Agri. Circ. 730. 90 p.
Denman, Charles E., W. C. Elder, and V. G. Heller. 1953. Performance of weeping
lovegrass under different management practices. Okla. Agri. Exp. Sta. Tech. Bul.
T-48. 18 p.
Leigh, J. H. 1960. Some aspects of the anatomy, ecology and physiology of Eragrostis.
Unpublished Ph.D. thesis, Univ. Witwatersrand, Johannesburg.
Leigh, J. H. 1961. The relative palatability of various varieties of weeping lovegrass
(Eragrostis curvula [Schrad.] Nees). J. Brit. Grassl. Soc. 14:135-140.
Raymond, W. F. 1964. The efficient use of grass. J. Brit. Grassl. Soc. 19:81-89.
Scott, J. D. 1956. The study of primordial buds and the reaction of roots to defoliation as
the basis of grassland management. Proc. 7th Int. Grassl. Congr. 479-487.
Scott, J. D. and J. W. Rabie. 1956. Preliminary studies on growth and development of
Eragrostis curvula and Themeda triandra. S. Afr. J. Sci. 55:207-210.
Steinke, T. D. and P. de V. Booysen. 1968. The regrowth and utilization of carbohydrate
reserves of Eragrostis curvula after different frequencies of defoliation. Proc.
Grassl. Soc. S. Afr. 3:105-110.
Questions and Answers
Q.
What is the difference between the Oklahoma City and Woodward areas on
growth and time of cutting?
A.
Gauge this on when the growth starts. At Woodward, growth starts during late
April. During the last week, we get significant growth. Oklahoma City would be
about two weeks ahead of Woodward. Rainfall and growing conditions are better
around Oklahoma City, so growth will be faster.
Q.
Do you fertilize after each cutting?
A.
Yes, this is recommended.
8
Q.
How much fertilizer do you apply?
A.
In our case, where we have drought, overfertilization can reduce stands. Thirty
pounds of actual nitrogen per acre per application, or whatever the plant can use
in about six weeks.
Q.
How far north is weeping lovegrass adapted?
A.
Woodward, Oklahoma, is on the northern limits. The northern border of Oklahoma is considered the limits at present. The limits depend on moisture and
temperature.
Q.
What is a shoot?
A.
It is a stem growth that will produce a seed head. It can be related to a tiller in
wheat. A shoot can be an individual plant. This plant has buds that produce more
growth—called shoots.
9
Cytogenetics of Eragrostis
L. J. Streetman1
The genus Eragrostis is composed of approximately two hundred eighty species
and is one of the most widely distributed genera of grasses in the world. A wide variety of
forms or varieties exists within many of the species. Quite often this wide range of types
has led to confusion when research data of various workers are compared.2 Polymorphism and the existence of integrating types between species prompted de Winter (3) to
revise the taxonomy of E. curvula (Schrad.) Nees to include E. chloromelas Steud. and E.
robusta Stent. Leigh later suggested that for pasture purposes, strains of E. curvula be
grouped into five types: curvula, chloromelas, robusta blue, robusta green, and robusta
intermedia. This classification was based primarily on leaf color, texture and size, inflorescence, and growth habit.
Species of Eragrostis were first introduced into the United States in the early
1930s, and several of these have been used extensively for reseeding the arid and semiarid rangeland of the Southwest (1, 2).
The species that have been of particular importance include E. curvula, E.
chloromelas, E. lehmanniana Nees, and E. superba Peyr. Most of the lovegrasses are
prolific seed producers, a characteristic almost indispensable for successful range revegetation. Their ability to green up earlier in the spring and remain green in the fall later
than common native grasses also enhances their usefulness.
Cytogenetic investigations of grasses serve two primary purposes: (a) to furnish
basic data which can be used in connection with morphological data in studies of taxonomy and phylogeny; and (b) to provide fundamental information necessary for improvement by breeding. This report is divided into two phases; chromosome numbers and
microsporogenesis and mode of reproduction of several Eragrostis species.
Chromosome Numbers and Microsporogenesis
Chromosome complements of five morphological types of E. curvula (curvula,
chloromelas, robusta blue, robusta green, and robusta intermedia) ranged from the tetraploid (2n = 40) to the octaploid (2n = 80) level.
Neither diploid (2n = 20) or aneuploid plants were found in any of the strains
studied. Chromosome numbers associated with the various morphological types were as
follows: curvula (2n = 40), robusta green (2n = 60), robusta blue (2n = 70), and
chloromelas (2n = 40, 80).
1. This study was conducted while the author was Cytogeneticist, Hoblitzelle Agricultural Laboratory,
Texas Research Foundation.
2. Leigh, J. H. Some aspects of the anatomy, ecology, and physiology of Eragrostis. Ph.D. Thesis. Univ. of
Witwatersrand. Johannesburg. 1960.
10
Meiotic behavior of the 2n = 60, 70, and 80 chromosome plants was highly
irregular. Numerous lagging chromosomes at anaphase I resulted in unbalanced chromosome disjunctions; therefore, a high frequency of the microspores were destined to be
nonfunctional or to possess aneuploid numbers.
Morphological uniformity and constant chromosome numbers of plants with
highly irregular meiosis support evidence that the E. curvula complex reproduces by an
apomictic mechanism. There appears to be little doubt that the basic chromosome number
of the genus Eragrostis is X = 10.
Mode of Reproduction
Cytological data obtained indicate that E. superba reproduces sexually. Megasporogenesis and embryo sac development is completely normal, the end result being a
gametophyte of the typical “Polygonum type.” Supporting these cytological data are
results from seed-set studies, Table 1, in which only fourteen seed per inflorescence were
set under space isolation, as compared to six hundred seventy-four when allowed to openpollinate. In addition, a space-planted progeny test at Texas Research Foundation displayed considerable variability for such characters as inflorescence type, growth habit,
rust resistance, leafiness, and plant height. Therefore, on the basis of both cytological and
field studies, it is postulated that E. superba is sexual and cross-pollinated.
On the other hand, E. chloromelas, E. lehmanniana, and E. curvula are considered
to reproduce apomictically. The mechanism appears to be diplospory with an Antennariatype embryo sac resulting from two or more mitotic divisions of the megaspore mother
cell. Since megaspores and disintegration of megaspores were readily detected in the
sexual species, E. superba, the absence of these developmental phases in ovules of these
species is strong evidence supporting the apomictic concept.
Pollination appears to be necessary for seed formation since embryos did not
develop until several hours after anthesis. Field studies indicated that seed-set by plants
under space isolation is equally as good as when plants are allowed to open-pollinate,
Table 1. Spaced plants from open-pollinated seed of these three species yielded no recognizable variants. Although the possibility of sexual reproduction with the species being
completely self-pollinated cannot be precluded, it is postulated on the basis of extensive
cytological observation that the reproductive mechanism is diplospory followed by
pseudogamy.
11
Table 1. Average number seed produced by five Eragrostis species under space isolation
and open pollinated conditions1
Species
E. Chloromelas
E. Curvula
E. Lehmanniana
E. Superba
E. Bicolor
Space Isolation
Avg. Seed/
No. Panicles
Panicle
28
570.4
23
516.3
50
229.0
37
13.7
42
1.0
Open Pollination
Avg. Seed/
No. Panicles
Panicle
30
624.9
30
625.4
30
584.7
30
674.2
30
592.9
1
Studies conducted by Neal Wright, Research Agronomist, and L. J. Streetman, formerly
Research Agronomist, USDA-ARS, Tucson, Arizona.
Summary
The results of these studies suggest that there could be some merit to grouping
those strains considered to be E. chloromelas under the species E. curvula, as has been
done previously (3). In this same light, E. lehmanniana would also have to be considered
a variety or form of E. curvula. The author has observed plants considered to be E.
curvula with inflorescences similar to both those of E. chloromelas and E. lehmanniana.
Within a given form, however, all plants remain true to type. This is only one of the many
characters which seem to provide definite links between the three species. Nevertheless,
recognizing that there are many intermediate forms making it difficult to demarcate these
species, it is felt that taxonomic revision of these species has been premature.
The plant scientist apparently can do little to improve varieties or strains of these
species using conventional breeding techniques, such as crossing and progeny selection,
because of apomictic reproduction. However, when useful strains exist within available
plant material, as is the case with this complex genus, varieties can be channeled to
farmers and ranchers immediately after thorough testing, thereby circumventing several
years of breeding work. This has happened with weeping lovegrass.
12
Literature Cited
Anderson, D., L. P. Hamilton, H. G. Reynolds, and R. R. Humphrey. Reseeding desert
grassland ranges in southern Arizona. Ariz. Exp. Station Bulletin 249. 32 pp.
1957.
Crider, F. J. Three introduced lovegrasses for soil conservation. U.S. Dept. Agr. Circ.
No. 730. 1945.
DeWinter, B. Eragrostis Beauv. The grasses and pastures of South Africa. Central
News Agency. Union of South Africa. 132-184. 1955.
13
New Varieties of Weeping Lovegrass through
Plant Evaluation and Selection1
Paul W. Voigt
Research Geneticist
Woodward, Oklahoma
Weeping lovegrass, Eragrostis curvula (Schrad.) Nees, is a highly variable species (deWinter, 1955). It includes material previously recognized as Eragrostis
chloromelas Steud. and Eragrostis robusta Stent. (Leigh, 1961b). Several other species
including Eragrostis planiculmis Nees, Eragrostis lehmanniana Nees, and Eragrostis
barbinodis Hack. are also closely related to E. curvula (deWinter, 1955). Because of its
apomictic mode of reproduction (Brown and Emery, 1958; Streetman, 1963), E. curvula
consists of many true breeding strains or types. Some of these types have been given
names (Leigh, 1961b). However, there appear to be many intermediates. Since only two
types of E. curvula will be discussed here, I will not attempt to classify the vast phenotypic variability within it.
The type of greatest importance in Oklahoma and Texas is the weeping or curvula
type (Leigh 1961b). In parts of New Mexico and Arizona, the boer or conferta type is
important. Although this type was previously known as E. chloromelas, it is now identified as E. curvula var. conferta. Lehmann lovegrass, E. lehmanniana, is also of importance in New Mexico and Arizona. However, as described later, recent events indicate a
decreasing role for this species during the next few years.
Crider’s extensive observations (1945), along with data collected at the Southern
Great Plains Field Station and other locations, indicate that, in general, weeping lovegrass
is the most productive and most winter-hardy of the three grasses. Boer lovegrass is
intermediate in forage production and the most drought hardy once established. Lehmann
lovegrass produces less, and more stemmy, forage than boer lovegrass and is the least
winter hardy. However, it has the advantage of being easier to establish under low rainfall
conditions and is the most seedling drought tolerant of the three grasses.
Varieties Today
Weeping lovegrass: Much of the common weeping lovegrass available today
derives from the SCS strain A-67. The common weeping lovegrass used in tests at Woodward was originally obtained from an old stand of A-67. This and other common seed
from long-time stands in the northern regions of lovegrass adaptation has proven to be the
most winter-hardy material available today.
1. Cooperative investigations of the Crops Research Division, Agricultural Research Service, U.S. Department of Agriculture, and Oklahoma Agricultural Experiment Station. Published with the approval of the
Director, Oklahoma Agricultural Experiment Station, as Manuscript No. 2006.
14
Several strains of weeping lovegrass have been selected and maintained in South
Africa. Leigh (1961c and 1967) has reported that differences within the curvula type were
not apparent. He stated, “It would be preferable to regard all similar strains as being
identical, unless significant differences can be demonstrated between them.” However,
our results (Voigt, et al., 1970) demonstrated significant differences within the curvula
type. Ermelo weeping lovegrass is one of the South African strains. It was selected by C.
C. Liebenberg and has been widely used for hay production and, to a lesser extent, for
grazing (Davidson, 1965). Most weeping lovegrass research in South Africa has been
conducted with this strain (Leigh, 1961b).
Studies at Woodward indicate that Ermelo, of the type promoted by the Texas
Research Foundation, is taller, later in maturity, and has a slightly wider leaf than common derived from A-67. This Ermelo is also more palatable than common in summer
grazings, but it is slightly less winter hardy. Unfortunately, not all so-called Ermelo has
these characteristics. One lot of Ermelo that I studied appeared no different from common. Originally, it was obtained by a reputable seedsman directly from South Africa.
Thus, Ermelo obtained from a reputable source will not necessarily be identical to any
other lot of Ermelo. Extra money paid for Ermelo on the tag will not guarantee Ermelo in
the bag.
‘Morpa’ weeping lovegrass is a new variety of weeping lovegrass recently released by the Oklahoma Agricultural Experiment Station and Crops Research Division,
Agricultural Research Service, U.S. Department of Agriculture. Morpa was selected for
its greater palatability relative to other weeping lovegrass strains. Its name is derived
from the two words more palatable. Morpa is more palatable than common and Ermelo in
summer grazings. However, it is very similar to Ermelo in appearance. Morpa is equal to
or better than any other weeping lovegrass strain tested in forage yield (Denman, 1964;
Denman et al., 1965; Huffine and Denman, 1963; Huffine et al., 1962). It was released
because of its greater economic potential. In a three-year grazing trial, Morpa produced
12 percent more gain per head than common (Voigt, et al., 1970). This significant increase, under the management system used, could produce an additional $12 of profit per
acre (Shoop, McIlvain, and Voigt, 1970). Thus, Morpa
1. produces more gain per head and profit per acre than common;
2. is equal to or better than common in all important characteristics except for a
slight reduction in winter hardiness; and
3. provides growers and seedsmen, for the first time, a weeping lovegrass variety
of proven type and potential relative to common.
A few thousand pounds of Morpa foundation seed should be available later this
year, and several thousand pounds of certified seed should be available late in 1971. The
importance of buying certified seed cannot be overemphasized. It is your best guarantee
of getting what you pay for.
Boer lovegrass: ‘A-84’ boer lovegrass was officially released in 1950 (Hanson,
1965). It was first introduced into the United States in 1932 and has been widely grown
15
in its area of adaptation for many years (Crider, 1945). The characteristics of boer
lovegrass mentioned earlier are based on this one variety.
‘Catalina’ boer lovegrass is a new variety selected for its seedling drought tolerance. It is equal to ‘A-68’ lehmann lovegrass in this respect. Catalina produced stands
equal to lehmann lovegrass at some locations and better than A-84 boer lovegrass at all
locations (Wright and Jordan, 1970). Catalina also produces more and better quality
forage than lehmann lovegrass. Catalina is expected to replace A-84 boer lovegrass and
partially replace A-68 lehmann lovegrass.
Varieties Tomorrow
The keys to success in perennial forage grass breeding have been well discussed
elsewhere (Hanson and Carnahan, 1956). I will attempt to illustrate how four of these
apply to selection in E. curvula. These keys are as follows:
Selection of an appropriate goal
Selection of methods to obtain this goal
Use of large and diverse source populations
Thorough evaluation of plant materials
Selection of an appropriate goal depends on the weaknesses of the grass under
consideration. It also depends on the availability of, or the possibility of developing, the
necessary methods for evaluating the source population. These methods must be quick,
precise, and inexpensive so that large populations can be screened. Large and genetically
diverse source populations are necessary so that the probability of finding the desired
traits will be high. Also, the selections must be thoroughly evaluated so that valuable
materials will not be discarded.
The recent publication of Wright and Jordan (1970) is a good illustration. Wright
(1964) concluded that the characteristic most limiting to the use of boer lovegrass was its
establishment in the semiarid and arid areas where it is otherwise well adapted. However,
recognition of this fact did little good until an effective method for evaluating material
was available. Wright (1961) devised a program-controlled environmental growth chamber to fill this need. Although his source population was relatively small, he did find one
selection with a high level of seedling drought tolerance. I have previously mentioned the
result of this well-planned effort, the release of Catalina boer lovegrass.
We have long known that in Oklahoma and North Texas weeping lovegrass is one
of the easiest perennial grasses to establish, that it has a high production potential, and
that it produces good seed yields. Also it does not have any disease or pest problems.
More recently, we have learned that weeping lovegrass is very responsive to management
practices such as burning, fertilization, and rotation grazing. The most limiting characteristic of this grass appears to be forage quality.
16
As I described earlier, selection for palatability has produced a new variety of
weeping lovegrass with higher forage quality (Voigt et al., 1970). Additional gains in
forage quality appear possible. Thus the primary goal of the lovegrass selection program
at Woodward is to increase the forage quality of weeping lovegrass while maintaining its
other desirable characteristics. A secondary objective is to maintain or, if possible, increase its winter hardiness.
Possibly the desired combinations of traits will not be found in this apomictic
species. Future improvements may depend on our ability to make crosses between different strains and to recombine their desirable characteristics. As a first step toward this
goal, we established a separate program to find a sexual strain of E. curvula. I am happy
to report that we have been successful in this effort (details will be published elsewhere).
However, chances for short-run improvement rest primarily in evaluation and selection
within existing strains.
Several techniques for the evaluation of forage quality have been developed.
However, a breeder will usually not have the resources to develop and standardize such
tests on his own. A team approach is essential. I am fortunate to be working with Dr.
Lavoy Croy at Oklahoma State University. Through his efforts, we are starting to evaluate a large number of E. curvula selections for in vitro digestibility. We are also continuing a program of palatability evaluation with steers provided by my co-workers at Woodward. Other methods (e.g., chemical analysis) can be of value but are beyond our capabilities at present.
Because selection is limited to existing apomictic strains, large and genetically
diverse populations are doubly important. A negative relationship between winter survival and palatability and between winter survival and leaf width indicates that the
desired combination of characters may be hard to find.2
Leigh (1961c) has suggested that the weeping type is not the best type for certain
management situations. He has proposed that research on other types of E. curvula should
be carried out under a variety of soil and climate conditions (Leigh, 1967). The proven
value of weeping, boer, and lehmann lovegrass in different moisture and temperature
environments lends support to his suggestion. Results at Woodward (Shoop et al., 1970;
Voigt et al., 1970) have also demonstrated important differences within types. The evidence
indicates that evaluation should be based on the widest possible genetic diversity.
In the breeding program at Woodward, we have attempted to obtain the widest
possible sample of E. curvula and other closely related species. These populations have
been screened only for purity of type and for a moderate level of winter hardiness.
Screening for winter hardiness has reduced the number of selections about one-third. The
large amount of phenotypic variability remaining leads me to hope that a great amount of
genetic variability for forage quality remains. I believe that our results will indicate which
selections may be of immediate agricultural value and which may have value in future
2. Unpublished results.
17
crossing programs. Because we have not selected for plant type in our source populations, we will have to select carefully for the desirable weeping lovegrass characteristics
along with forage quality.
Evaluation must be extensive not only within the source population, but must also
be extensive over time. The many unanswered questions in this area create additional
problems. Can we maximize our detectable differences in digestibility by sampling at
relatively mature stages of growth (a poor pasture management procedure), or will better
results be obtained with more frequent sampling? How many samples per year are needed
to adequately reflect seasonal trends that may differ from selection to selection? How will
year-to-year variability affect relatively small, but important differences? Will values for
spaced plants be indicative of those in wide or narrow rows? Leigh (1961a) has observed
that E. curvula spaced-plant forage yields did not reflect broadcast plot yields. Clearly,
we still have a lot to learn about the best ways to make forage quality evaluations.
It is hard to predict when the next weeping lovegrass variety will be released.
Selection and evaluation of Morpa took seventeen years. Although this process might
have been speeded up slightly at several points, fourteen to sixteen years has not been
considered unreasonable for the development of a perennial forage grass variety (Hanson
and Carnahan, 1956). This may appear to be a long time to those not familiar with forage
crop breeding. However, the problems of long-term adaptation evaluation and the necessity of testing each planting for at least three to four years preclude much shortening of
this development period. Although it will be a number of years before the Southern Great
Plains Field Station will be in a position to announce the release of another new variety, I
feel confident that additional improvements in forage quality are possible. I believe these
improvements will mean both a wider role for weeping lovegrass and more profits to
those who use it.
References
Brown, W. V. and W. H. P. Emery. 1958. Apomixis in the Gramineae:
Panicoideae Amer. J. Bot. 45:253-263.
Crider, F. J. 1945. Three introduced lovegrasses for soil conservation. U.S. Department
of Agriculture. Circ. No. 730. 90 p.
Davidson, R. L. 1965. Management of sown and natural lovegrasses. J. Range Manage.
18:214-218.
Denman, C. E. 1964. Forage crop production studies progress report, 1963. Oklahoma
State University. Processed Ser. P-479. 27 p.
Denman, C. E., H. E. Reeves, R. N. Ford, and C. W. Thurman. 1965. Forage crop
variety trials progress report, 1964. Oklahoma State University. Processed Ser.
P-506. 37 p.
18
Hanson, A. A. 1965. Grass varieties in the United States. U.S. Department of
Agriculture. Agriculture Handbook No. 170. 102 p.
Hanson, A. A. and H. L. Carnahan. 1956. Breeding perennial forage grasses. U.S.
Department of Agriculture. Technical Bull. No. 1145. 116 p.
Huffine, W. W. and C. E. Denman. 1963. Forage crop production studies progress
report, 1962. Oklahoma State University. Processed Ser. P-442. 26 p.
Huffine, W. W., C. E. Denman, G. L. Duncan, J. H. Stritzke, and D. A. Hollier. 1962.
Forage crop production studies, biennial report of progress, 1960-1961. Oklahoma
State University. Processed Ser. P-410.
Leigh, J. H. 1961a. Behavior of certain varieties of lovegrass when grown as spaced
plants and in broadcast stands. Empire J. Exp. Agric. 29:265-268.
Leigh, J. H. 1961b. Leaf anatomy in certain strains of Eragrostis (Beavu.). J. S. Afr.
Bot. 27:141-146.
Leigh, J. H. 1961c. The relative palatability of various varieties of weeping lovegrass
(Eragrostis curvula [Schrad.] Nees). J. Brit. Grassl. Soc. 16:130-140.
Leigh, J. H. 1967. Comparisons between strains of Eragrostis curvula in South Africa.
Expl. Agric. 3:327-335.
Shoop, M. C., E. H. McIlvain, and P. W. Voigt. 1970. ‘Morpa’ weeping lovegrass:
More palatability, gain, and profit. (Manuscript in preparation.)
Streetman, L. J. 1963. Reproduction of the lovegrasses, the genus Eragrostis: I. E.
chloromelas Steud., E. curvula (Schrad.) Nees, E. lehmanniana Nees, and E.
superba Peyr. Wrightia 3:41-51.
Streetman, L. J. 1966. Ermelo lovegrass. Texas Research Foundation, Hoblitzelle
Agr. Lab. Bull. 25. 15 p.
Voigt, P. W., W. R. Kneebone, E. H. McIlvain, M. C. Shoop, and J. E. Webster. 1970.
Palatability, chemical composition, and animal gains from selections of weeping
lovegrass, Eragrostis curvula (Schrad.) Nees. Agron. J. (In press.)
Winter, B. de. 1955. Eragrostis Beauv. P. 132-184. In D. Meredith, ed. The grasses and
pastures of South Africa. Central News Agency. Union of South Africa.
Wright, L. N. 1961. A program-controlled environmental plant growth chamber. Arizona
Agr. Exp. Sta. Tech. Bull. 148. 31 p.
19
Wright, L. N. 1964. Drouth tolerance-program-controlled environmental evaluation
among range grass genera and species. Crop Sci. 4:472-474.
Wright, L. N. and G. L. Jordan. 1970. Artificial selection for seedling drouth tolerance in
boer lovegrass (Eragrostis curvula Nees). Crop Sci. 10:99-102.
Q.
What are the distinguishing characteristics of Morpa and other weeping lovegrass
varieties?
A.
Morpa can be distinguished from common quite easily if the two are growing
together. If you are familiar with them, and they are growing separately, head
color can be used to distinguish the Morpa from common, but it could not be used
to separate it from Ermelo. Morpa is very similar to Ermelo in appearance. They
have about the same leaf width differences. Side by side, Morpa and Ermelo may
have slight leaf width differences.
Q.
Have you found any of the more palatable robusta types that might have more
winter hardiness in the Woodward area?
A.
Most of the robusta types have not been winter hardy. A few have survived several winters at Woodward, but some of the winters were mild.
Q.
Is the sexual plant you have found a 20 chromosome that you had earlier?
A.
Yes, and I have since found two other strains. These are less winter hardy and
have not gone through the winter at Woodward. They are boer or conferta type
plants. I now have a fourth strain, which is an additional diploid, which is not a
boer or conferta plant. It could be intermediate between a typical conferta and
curvula. This is the most winter hardy of the sexual material I have seen. It appears to have crossed with another of the new sexual plants, which was a small
short conferta which was probably inbred. This gave quite robust outcross material.
Q.
How can we producers be assured we are getting the correct variety?
A.
We realize there has been a problem of this in seed trade. The best approach is
buy certified seed of the variety.
20
Weeping Lovegrass Establishment
and Management of First Year Stands
Agricultural Division, Noble Foundation
Many methods of planting weeping lovegrass have been used, both in general
research and on farms and ranches. The grass lends itself well to a wide variety of procedures. However, the more accurate and concise procedures, along with proper timing and
other factors, lead to the best establishment, good first and successive year production,
and, therefore, most useful pastures. In an extensive pasture such as this, we are not
interested in just an acceptable stand, but one that can be profitably managed for a lifetime. A half stand requires basically the same cost management for much less production.
One should remember that the establishment year is a year getting ready for years to
come. The better, more consistent procedures are the ones of interest here. More discussion can be studied on most establishment facets in other publications (2, 5).
Adaptation: Weeping lovegrass can be grown on most nonsaline, well-drained
soils. It is better adapted to sandy soil than clay, but production and use on clay loam has
been good. Geographically, it is better adapted from the Kansas-Oklahoma line, south
and east (2). It will not tolerate exceedingly regular below 0o F temperatures.
Seedbed: Regardless of the method used, the best general final seedbed should be
clean, firm as an alfalfa seedbed, and fresh at planting. This is in cases where mulch is
not needed. Seedbed firmness cannot be overemphasized. If the seedbed has been rained
on prior to planting, it should be tilled to limit germination and establishment of weedy
plants and to prepare a better environment for weeping lovegrass seed. The seedbed is not
complete until after the planting operation. Weeping lovegrass will not emerge to a
satisfactory stand until after another rain. It is wise to plant when good subsoil moisture is
present, but with a dry surface soil. Precipitation will settle the soil around the seed and
“meet the moisture” for good emergence. Loose seedbeds equal slow and spotty establishment.
Mulches should be used only for erosion control. Mulches themselves may actually reduce weeping lovegrass stand emergence, but by controlling erosion, the final
result is better than no mulch. Acceptable mulch material includes previous summer
crops, winter small grains killed by light tillage, and even old weedy residue. Regardless
of the mulch used, it is best to freshen the soil surface in some manner before planting for
better seed environment.
Planting dates: Spring planting can be done anytime after the frost season has
passed. More germination and emergence occur in plantings done two to three weeks or
21
more after the last frost. By this time, temperatures are suitable for rapid germination and
growth after precipitation. The grass can be planted anytime during the growing season,
but incidence of failure is higher in midsummer plantings due to drought periods. The
best general planting date in central and southern Oklahoma is about April 15.
Fall planting is receiving interest, especially in areas where crabgrass, sandbur,
prairie threeawn, and other weedy annual grasses pose a serious competition threat in
spring and early summer plantings. Fall planted grass grows very rapidly the following
spring, providing it establishes well and does not winter kill. Fall plantings must be made
two to three months before frost to allow for precipitation and time for germination and
sufficient early growth. It appears that seeding rates for fall planting may need to be a
little higher than for spring planting because the length of time for successive germination is short in the fall. After weeping lovegrass germinates and emerges, it will grow in
cooler temperatures, but germination will be reduced at temperatures below 68o to 77o F
(7). In trials at Ardmore, Oklahoma, 70 percent of a 1968 fall planting on a sandy loam
soil survived the winter. Well-tillered plants generally survived, although differences in
tiller stage were not noted. The surviving plants regrew nearly as rapidly during spring as
older plants and, after one month’s growth, killed plant areas could not be detected. A
1969 fall planting on clay loam soil heaved out severely to result in only 8.6 percent
survival. Fall planting on clay soil appears unwise at present.
Rates: Rate of planting depends on row spacing and stand desired (Table 1). In
general, 10- to 14-inch rowed stands have performed well throughout most of Oklahoma.
These stands can be used for basically any forage need. Some operators prefer a closer 6to 7-inch row, while others are biased for thick broadcast stands. Thick broadcast stands
or thick narrow rows are not as desirable as wider rows or thinner broadcast stands. The
smaller individual plants of thick stand are much more slow to regrow after clipping and
are more quickly and drastically set back by drought. No concise yield data is available,
but it is likely that very thick stands are lower in production after full establishment than
10- to 14-inch rowed stands. One pound of seed evenly distributed will equal about
thirty-five seeds per square foot.
Table 1. Seeding Rates of Weeping Lovegrass for Forage (Pure Live Seed Basis)
Pounds
PLS/Acre
0.5 to 1
2 to 3
3 to 4
3 to 6
Stand Type
36-inch row
10- to 14-inch row
6- to 7-inch row
Broadcast
A good stand should occupy 80 percent or more of the row area by the end of the
first season.
22
Varieties: Three basic choices in weeping lovegrass variety or strain are available.
They are common, ‘Ermelo’, and ‘Morpa’. ‘Ermelo’ and ‘Morpa’ are rated more palatable than common (2, 4, 5). ‘Morpa’ has given better animal gains in USDA tests than
common. Tests of animal gain on ‘Ermelo’, versus common or ‘Morpa’, are not known.
There are apparently no major differences in forage yield. Regardless of the variety used,
all improved management practices must be used for good results.
Starter fertilizer and first year nitrogen topdressings: Starter fertilizer applied at
or near planting time has been studied and observed several years. This is a very important facet of early plant growth and production. Starter fertilizer response has been very
good from central and southern Oklahoma. Early fertilizer application increases early
growth, production, and quality, and helps invigorate the plants for the seasons to come.
No concise measurement of prolonged effects has been made, but the effect of only one
application can be seen for one to several seasons.
Methods of application and rates vary considerably and are too numerous to fully
discuss here. In general, very good results have been received from banded applications
in central to southern Oklahoma (2, 6). In 10- to 14-inch rows, rates of 10 to 20 pounds
per acre of actual nitrogen and 20 to 40 pounds per acre of phosphorus have been very
good on phosphorus deficient soil. Potassium, if needed, is added at similar rates to
phosphorus. Soil tests are needed to determine phosphorus and potassium needs. Several
other methods are discussed in Weeping Lovegrass Management (2). In drier northwestern Oklahoma, starter fertilizer damage has been severe when used, and rates are much
lower at about 5-10-0 in 12-inch rows (3). In southern Oklahoma, we may get slight
germination and seedling damage from banded fertilizer, but it is so quickly and drastically overcome that it is not worth considering.
During 1969, a very dry summer, average responses to banded starter fertilizer
and nitrogen topdressing from four areas were as depicted in Table 2. The pastures were
planted during the first half of April. All areas received a disk-in application of 0-47-47 or
0-55-55 per acre. Starter fertilizer of 18-22-0 or 20-24-0 per acre was banded with the
seed on or near the soil surface and both pressed firmly into the soil with press wheels;
planting was in 10-inch rows. Ammonium nitrate to equal 78 pounds of actual nitrogen
per acre was applied in the 4- to 6-inch seedling stage on May 23. This was twenty-one
days before the last effective growing season rainfall on June 13. Good rains fell again
during mid-October. Due to dry weather, minimal response was received from the
topdressing. Visual responses were still quite evident early in the 1969 growing season.
First year yields of 4,000 to 6,000 pounds per acre, oven-dry weight, are often obtained in
this region. Early visual response of 1970 plantings is much greater than in 1969. These
plots received 18-46-0 per acre in 10-inch rows without any disk-in phosphorus and
potassium.
23
Table 2. Starter Fertilizer Response on Weeping Lovegrass near Ardmore, Oklahoma—1969
% Stand
by Fall
83
89
84
90
Treatment1
No banded starter
Banded starter (only)
Nitrogen topdressed (only)
Banded starter and nitrogen topdressed
Pounds/Acre
(Oven-Dry)
764
1,456
1,387
2,210
1
All received preplant, disk-in, phosphorus-potassium application.
Nitrogen topdressings are vitally important for best development and production
of first year stands. Generally, the first topdressing comes when the stand is assured and
the first crop of seedlings is 4 to 6 inches tall, regardless of the rate of banded starter
fertilizer. Earlier or later topdressing can be done. If midseason haying or grazing is done,
a second application can be made if moisture is adequate. Almost invariably at least one
application is made, and it is 50 to 75 pounds per acre actual nitrogen from ammonium
nitrate.
Some operators prefer to sacrifice a little production and apply first year fertilizer
at two periods, the first being a disk-in or plowdown of needed phosphorus and potassium, and the second being the nitrogen topdressing discussed previously. With this
procedure, the grass establishes without the benefit of banded starter.
Seed treatment: USDA research at Woodward, Oklahoma, has shown seed treatment with copper carbonate dust to result in about 25 percent better seedling emergence
and vigor (3). This would indicate to some degree that seedling diseases influence stands,
and seed treatment may need to be widely carried out. In southern Oklahoma, up to over
80 percent of emerging stands have been killed on well-drained clay land by what appeared to be damping off. Copper carbonate is presently difficult to locate, and other
fungicides need to be tested on weeping lovegrass.
Planting equipment: Basically any planting equipment that will accurately distribute small seed of weeping lovegrass can be used. Broadcast planting can be done with
methods varying from hand-operated seeders to airplanes. With broadcast planting and
some drilled planting, the soil should be rolled to firm the soil around the seed. Failure is
more apt to occur when the soil is left loose around the seed.
Rowed plantings can be planted with small seed planters including regular grain
drills with small seed boxes, stubble mulch drills with small seed boxes, sod pasture drills
with small seed boxes, cultipacker planters, Planet Jr. boxes, and special planters available from soil conservation districts. Fertilizer boxes on the equipment allow for banded
fertilizer placement. Major considerations on any of the equipment are
1. plant seed on the soil surface to no deeper than 1/2 inch;
24
2. distribute seed and fertilizer accurately;
3. leave soil surface around seed as firm as possible; press wheels work better than
drag covering.
Much weeping lovegrass has been successfully planted in central and southern
Oklahoma with grain drills with small seed boxes. These drills are altered to allow the
fertilizer to be drilled into the soil slightly with the seed placed above it, as was illustrated
to be better in early research (6). The small seed spout is fastened behind the shoe 4 to 6
inches (Fig. 1). The rest of the drill is operated normally. With this method, the fertilizer
is drilled into the soil 1/2 to 1 inch deep. Normally, the soil covers the fertilizer before the
seed is placed on the surface behind the shoes. Press wheels or drags will firm the soil in
the shallow furrow, or all further firming and covering can be done by future precipitation. Press wheels appear to be better than drags or no firming.
Excellent stands have been
established with stubble mulch drills.
With this equipment, the seed and
fertilizer are banded on or near the
soil surface with minimum seedbed
disturbance. Press wheels firm the
seed-fertilizer row and make a slight
furrow in firm soil. Precipitation
causes light silting over the furrow
for seed covering, and good stands
emerge. As with all methods, the
seedbed is not complete until after
planting, and, in this case, the firmness of the soil in the row is ideal,
and leaving the soil friable between
the rows reduces weed infestation for
awhile.
The importance of row
planting and pressing the soil after
planting has been drastically shown
with this drill. In cases where the
seeds were broadcast on the fresh soil
surface and not rolled, very little
stand is evident, compared to the row
Figure 1. Diagram of starter fertilizer and
planting and pressing areas. Firming
weeping lovegrass seed placement with
the soil under and around the seed
regular grain drills, pasture drills, and stubble
cannot be overemphasized. Anyone
mulch drills
can witness this by observing that the
seedling establishment will usually
be the quickest and best in tire tread marks.
25
Weed competition and control: Weeping lovegrass is rated as very competitive to
weedy competition. However, in the young stages, severe competition from weeds and
weedy grasses can drastically reduce yields or can completely eliminate stands.
Broadleaf weeds can be readily controlled with 2,4-D. Many young weeds, less
than 2 to 3 inches tall, can be controlled with 1/4 to 1/2 pound of 2,4-D per acre with little
or no harm to young weeping lovegrass. Total kill may not result, but control would be
acceptable. If the weeds must be sprayed with 1 pound of 2,4-D per acre, the weeping
lovegrass seedlings should be beyond the four- to six-leaf stage for safety. In tests near
Ardmore, Oklahoma, 2,4-D low volatile ester applied at 1 pound per acre to weeping
lovegrass in the preemergence and one- to two-leaf stage resulted in 31 percent and 11
percent reduction in midsummer stand, respectively.
It was also observed that six to seven western ragweed per square yard reduced
stand and production by 50 percent. In more severe cases, 80 percent of the stand was
lost. Laboratory tests with extract of western ragweed showed that weeping lovegrass
germination and early seedling growth in the extract was 17 percent of that in distilled
water. There is more to weed competition than light, nutrients, and water.
Annual grasses, such as crabgrass and others, often severely influence establishing stands of weeping lovegrass. This weed was studied at Oklahoma State University
and was shown to reduce first and second year production by 50 percent (1). Sod reserves were severely affected.
The only possible control of these unwanted grasses is by utilization. Under
lower fertility regimens, cattle have grazed crabgrass with less grazing on weeping
lovegrass. After grazing for crabgrass control, deferment of use favored weeping
lovegrass. Under higher fertility, all plants were grazed and less benefit was noted,
although utilization was better than heavy competition. Mowing periodically may also
help, but heavy growth mowed and left on the area can kill weeping lovegrass. In these
weedy grass competition pastures, it is better to plant after a crop or two of the weeds are
killed by cultivation. Weeping lovegrass will then make a better, more rapid growth.
First year utilization: Weeping lovegrass should never be continuously grazed
during the first year, but one or two utilization periods are usually permissible. Under
weedy grass competition mentioned previously, more regular utilization may be necessary for weed control.
If the new grass makes sufficient growth for a hay crop or grazing period by
midsummer, this crop can be taken. After this utilization, the grass should be topdressed
with nitrogen, and further use deferred until fall or winter. In such a system on shallow
soil near Healdton, Oklahoma, during 1968, twenty-three bales of hay plus 107 cow-days
per acre as winter roughage were realized. On a moderately deep sandy soil near Ada,
Oklahoma, over 440 heifer-days per acre were realized from two grazing periods on a
first year stand in 1967. During dry 1969, over 100 cow-unit-days, as winter roughage,
were realized on a first year stand at Ardmore, Oklahoma.
26
If a pasture will produce 2 to 3 tons of forage the first season, it is probably best
to utilize it in two periods rather than wait until winter. In contrast, in certain areas or on
certain soil sites and under low rainfall conditions, if no more than 1 to 2 tons of forage
are produced, it is well to leave it all for winter roughage. Regardless of the utilization
procedure used, it appears best to go into dormancy with at least 6 inches of growth
present. Under this system, the plant will emerge the following spring in a vigorous state.
References
Bryan, G. G. and W. E. McMurphy. 1968. Competition and fertilization as
influences on grass seedlings. J. Range Manage. 21:98-101.
Dalrymple, R. L. Weeping lovegrass management. Noble Foundation. Ardmore,
Oklahoma. Bulletin. 39 pp.
McIlvain, E. H. and Marvin Shoop. U.S. Southern Great Plains Field Station.
Woodward, Oklahoma. Personal communication.
New weeping lovegrass released. 1970. Oklahoma certified seed news. Oklahoma
Crop Improvement Assn. Stillwater, Oklahoma. 15:3, No. 2.
Streetman, L. J. 1966. Ermelo lovegrass. Texas Research Foundation. Renner,
Texas. Bulletin 25. 15 pp.
Thompson, L. F. and C. C. Schaller. 1960. Effect of fertilization and date of planting
on establishment of perennial summer grasses in southcentral Oklahoma. J.
Range Manage. 13:70-72.
Toole, V. K. 1938. Germination requirements of the seed of some introduced and
native grasses. Proc. Official Seed Analyst. 33rd A. Meeting. P. 227-243.
Q.
Were your seeding rates based on pure live seed?
A.
Yes.
Q.
Does weeping lovegrass usually analyze high in germination and purity?
A.
Yes, good recleaned seed will test over 85 percent germination and close to 98
percent in purity.
27
Performance of Common Weeping Lovegrass in a Clipping Test
R. P. Bates
Noble Foundation
Ardmore, Oklahoma
Common weeping lovegrass, King Ranch bluestem, and three bermudagrass
varieties along with twenty experimental bermudagrass and bluestem strains were compared in a clipping test during 1967, 1968, and 1969. More detail concerning procedures
involved in this test is shown in Table 1.
Some of the more interesting trends involving common weeping lovegrass are as
follows:
1. During three years, Coastal bermudagrass has outyielded common weeping lovegrass
in forage production by an average of 10.6 percent. Common weeping lovegrass
outyielded Midland bermudagrass and King Ranch bluestem by 7.9 and 94.8 percent,
respectively (Table 2).
2. Fertilizer applications increased forage yields of common weeping lovegrass, Coastal
bermudagrass, Midland bermudagrass, and King Ranch bluestem by an average of 82
percent, 117 percent, 104 percent, and 102 percent, respectively (Tables 2 and 3).
3. Common weeping lovegrass produced more forage in April and May than Coastal
bermudagrass (Figs. 2 and 3).
4. Coastal bermudagrass produced more forage during late June, July, August, September, and October than common weeping lovegrass (Figs. 2 and 3).
5. The main forage producing period of common weeping lovegrass corresponds fairly
closely to the main rainfall period in Southern Oklahoma (Figs. 1, 2, and 3).
6. In this test, common weeping lovegrass began making growth in the spring about
three weeks ahead of Coastal bermudagrass (Figs. 2 and 3). In 1968, some experimental bermudagrass hybrids were nearly as early as the lovegrass (Fig. 4).
7. Percent dry matter at time of clipping was usually higher in common weeping
lovegrass than other grasses (Table 5).
8. Dry matter percentage in forage at time of clipping was negatively correlated with
protein, phosphorus, potassium, and calcium content of forage (Tables 6 and 7). This
is probably connected with fertilizer treatments.
9. Green common weeping lovegrass forage was usually lower in crude protein, phosphorus, potassium, and calcium content than other grasses (Tables 8, 9, 10, and 11).
28
10. Dry common weeping lovegrass forage collected on December 4 was higher in crude
protein and potassium than other grasses (Tables 8 and 10). On this date, lovegrass
forage contained a few green leaves, whereas bermudagrass forage was completely
brown.
11. Response of common weeping lovegrass to fertilizer was variable, depending on
nutrients in the soil, rainfall, etc. (Figures 5, 6, and 7).
12. The particular management of each grass according to its capabilities and characteristics may affect its yield and quality more than the difference among varieties grown
under the same management. A knowledge of capabilities and characteristics of each
grass is needed, however, in order to work out the most profitable or desirable management for various enterprises.
Table 1. Clipping Test Established May 1–3, 1967
Entries
17 Experimental bermudagrass hybrids
3 Experimental bluestem blends
5 Check varieties
Midland, Coastal, and Zimmerly Select bermudagrass
King Ranch bluestem
Common weeping lovegrass
Replications
(3) Three
Plot Size
Each plot was originally 10’ x 30’. Half of each plot was fertilized, making each
unfertilized or fertilized plot of each grass 10’ x 15’.
Clipping Procedure
Grasses were clipped with a rotary mower at a height of 3” to simulate rotational
grazing. The test is clipped when the most productive entries have reached a
height of 12” to 16”.
Soil Type
Fine sandy loam at Ardmore, Oklahoma.
29
Table 2. Three Year Summary of Oven-Dry Forage Yields in Pounds per Acre—1967–69
Total Annual Yields
1967
1968
1969
3-Yr. Avg.
No
No
No
No
Grass
Fert.
80-80-80
Fert.
135-30-15 Fert.
134-40-40 Fert. Fert.
Coastal
bermuda
3615
4213
3300
8447
1246 5076
2720 5912
Common
weeping
lovegrass
3424
3869
3760
7779
2040
5138
3075
5595
Midland
bermuda
2831
3509
3472
7401
1318
4643
2540
5184
K. R.
bluestem
1321
1453
1841
4539
1097
2623
1420
2872
Average
2798
3261
3161
7042
1425
4370
2461
4891
Table 3. Percent Increase in Forage Production with Fertilizer Applications
Grass
Common
weeping lovegrass
1967
1968
1969
Total
Forage
11.3
106.8
151.9
82.0
Coastal
bermudagrass
11.7
156.0
307.4
117.4
Midland
bermudagrass
12.4
113.2
252.3
104.1
K. R.
bluestem
10.0
146.6
139.1
102.3
30
Table 4. Oven-Dry Forage Yields in Pounds/Acre—Average of 1968–1969
Total of
Total of
May and June
July to October
Clipping
Clipping
Annual Total
Grass
No Fert.
Fert.
No Fert.
Fert.
No Fert. Fert.
Coastal
bermudagrass
780
3000
1493
3762
2273
6762
Common
weeping lovegrass 1388
3837
1513
2622
2901
6459
Midland
bermudagrass
1030
2812
1365
3211
2395
6023
K. R.
bluestem
499
1417
971
2165
1470
3582
Average
924
2767
1336
2940
2240
5707
Table 5. Percent Dry Matter in Forage at Time of Clipping—Average of 1968–1969
Average of
Average of
May and June
July to October
Clipping
Clipping
Annual Average
Grass
No Fert.
Fert.
No Fert.
Fert.
No Fert. Fert.
Coastal
bermudagrass
40.3
33.2
48.9
44.4
44.6
38.8
Common
weeping lovegrass 46.1
36.1
53.1
45.2
49.6
40.7
Midland
bermudagrass
42.1
34.4
50.6
43.9
46.2
39.2
K. R.
bluestem
35.3
26.8
48.3
39.9
41.8
33.4
Average
41.0
32.6
50.2
43.4
45.6
38.0
31
Table 6. Correlation Coefficients—1967
Dry Forage Yield
% Dry
%
Matter
Protein
Dry forage yield
.0044
.1338
% Dry matter
%
Phosphorus
-.1367
%
Potassium
-.0084
%
Calcium
-.1157
-.8350**
-.9173**
-.5401*
.3789
.5931*
.0741
% Phosphorus
.8328**
.6578*
-.6017*
% Protein
% Potassium
Table 7. Correlation Coefficients—1968
% Dry
% Crude
Dry Forage Yield Matter
Protein
Dry forage yield
-.5391**
.2331
% Dry matter
%
Phosphorus
.0838
-.5310**
-.3047*
% Crude protein
.4531**
% Phosphorus
32
%
Potassium
.6870**
.6303**
%
Calcium
.0833
-.4576**
-.4402**
.7142**
.4456**
.3359*
.3396*
% Potassium
.4340**
Table 8. Percent Crude Protein in Forage at Time of Clipping—1968
Average of
Average of
May and June
August and October
December 4
Clipping
Clipping
Clipping
No
No
No
Grass
Fert. 135-30-15 Fert. 135-30-15 Fert. 135-30-15
Coastal
bermudagrass
8.7
10.0
5.7
5.3
3.6
4.0
Average
No
Fert.
135-30-15
6.0
6.4
Common
weeping lovegrass 6.7
7.9
4.9
5.7
4.8
5.1
5.5
6.2
Midland
bermudagrass
8.7
9.7
5.9
5.7
4.4
4.8
6.3
6.7
K. R.
bluestem
7.9
8.9
5.3
6.5
4.3
4.5
5.8
6.6
Average
8.0
9.1
5.5
5.8
4.3
4.6
5.9
6.5
Table 9. Percent Phosphorus in Forage at Time of Clipping—1968
Average of
Average of
May and June
August and October
December 4
Clipping
Clipping
Clipping
No
No
No
Grass
Fert. 135-30-15 Fert. 135-30-15 Fert. 135-30-15
Coastal
bermudagrass
.21
.24
.21
.19
.06
.08
Average
No
Fert.
135-30-15
.16
.17
Common
weeping lovegrass .16
.18
.14
.16
.07
.07
.12
.14
Midland
bermudagrass
.21
.23
.21
.20
.07
.08
.16
.17
K. R.
bluestem
.19
.24
.23
.21
.08
.09
.17
.18
Average
.19
.22
.20
.19
.07
.08
.15
.17
33
Table 10. Percent Potassium in Forage at Time of Clipping—1968
Average of
Average of
May and June
August and October
December 4
clipping
clipping
Clipping
No
No
No
Grass
Fert. 135-30-15 Fert. 135-30-15 Fert. 135-30-15
Coastal
bermudagrass
.58
.84
.42
.50
.11
.17
Average
No
Fert.
135-30-15
.37
.50
Common
.63
.29
.40
.13
.30
.25
.44
Midland
bermudagrass
.52
.80
.43
.51
.10
.19
.35
.50
K. R.
bluestem
.62
.91
.51
.58
.11
.17
.41
.55
Average
.51
.80
.41
.50
.11
.21
.35
.50
Table 11. Percent Calcium in Forage at Time of Clipping—1968
Average of
Average of
May and June
August and October
December 4
clipping
clipping
Clipping
No
No
No
Grass
Fert. 135-30-15 Fert. 135-30-15 Fert. 135-30-15
Coastal
bermudagrass
.10
.14
.11
.11
.07
.07
Average
No
Fert.
135-30-15
.09
.11
Common
.11
.08
.09
.07
.09
.08
.10
Midland
bermudagrass
.11
.12
.10
.10
.07
.10
.09
.11
K. R.
bluestem
.11
.14
.09
.09
.09
.09
.10
.11
Average
.10
.13
.10
.10
.08
.09
.09
.11
34
Inches of
Rainfall
15
10
FIGURE 2 - Forage Production by Clipping Dates & Monthly Rainfall
1968
35
36
37
38
References
Bates, R. P. 1967. Forage yields from bermudagrass, King Ranch bluestem, and weeping
lovegrass. Samuel Roberts Noble Foundation, Inc., R-105.
Bates, R. P. 1967. Chemical analyses of bermudagrass, King Ranch bluestem, and
weeping lovegrass forage. Samuel Roberts Noble Foundation, Inc., R-108.
Bates, R. P. 1968. Chemical analyses of bermudagrass, King Ranch bluestem, and
weeping lovegrass forage. Samuel Roberts Noble Foundation, Inc., R-119.
Q.
With the actual nitrogen application at 135 pounds per acre, why was crude
protein content only 6 percent?
A.
The protein was an average of several clippings. Nitrogen was applied twice per
season. Right after an application, protein content was 10 to 12 percent, but later
the content would be 4 to 6 percent. This makes the protein content averages low,
but more frequent nitrogen application could keep the content higher. Low
rainfall periods also lowered protein content.
Q.
Are you recommending Coastal bermuda over Midland bermuda?
A.
Yes, in southern Oklahoma, if you are going to plant on a good soil and use good
management practices. We have had it at the Noble Foundation for about fifteen
years without winter kill problems. In some areas, under late plantings and dry
conditions, there may be some damage on first year plantings.
Q.
How would a combination of weeping lovegrass and Coastal bermuda perform?
A.
These have been used and work very well. The earliness of weeping lovegrass in
the growing season is quite advantageous.
39
Conservation Uses of Weeping Lovegrass (Eragrostis curvula)
Maurice D. Gamble
State Conservation Agronomist
Weeping lovegrass (Eragrostis curvula) is a perennial bunchgrass native of South
and East Africa. Its accession was established by the Bureau of Plant Industry in 1928
from a collection made in Tanganyika in 1927 (1). The first planting in Oklahoma was
made in a Soil Conservation Service grass nursery at Stillwater, Oklahoma, in 1935 (6).
While serving as an Agronomist with the Soil Conservation Service (1937-1941)
on the Cow-Creek Demonstration Project, Duncan, Oklahoma, an allotment of weeping
lovegrass seed for observational plantings was received in the winter of 1939. In the
spring of 1940, a number of such plantings were made in the area served by Cow-Creek
Demonstration Project, Duncan, and CCC Camps located at Duncan, Oklahoma, and
Rush Springs, Oklahoma. These camps were assigned to the SCS for soil and water
conservation work.
In the years of 1940-1945, while many field observations were in progress, seed
increase and research studies were initiated by the Oklahoma Agricultural Experiment
Station, Stillwater, Oklahoma, and the Red Plains Conservation Experiment Station,
Guthrie, Oklahoma (8).
From these pioneer plantings, there was a phenomenal expansion with bonanza
seed prices. It is understandable that more attention was given to seed production for sale
than to areas of adaptation, conservation uses, and management needs. Following this
period, a forage crop emerged of major importance in Oklahoma.
Since we will hear some of the best plant scientists in their field discuss forage
development and program management for weeping lovegrass, I shall confine the rest of
my remarks to the conservation uses of weeping lovegrass.
The conservation value of weeping lovegrass, in its area of adaptation, was
recognized early in Oklahoma (7). While the primary use is quality forage for livestock,
conservation use is enhanced by a number of factors such as the following:
1. It is adapted to a wide range of soil types.
2. It is easily, rapidly, and economically established.
3. It makes good growth at low levels of fertility and also responds rapidly to
nitrogen.
4. It has good drought tolerance, but is somewhat sensitive to prolonged low temperatures under dry conditions. Such damage would usually be confined to
northwest Oklahoma beyond Woodward, Oklahoma.
5. It is compatible with a number of other perennial plants such as most native
grasses, some Old World bluestems, and sericea lespedeza.
40
6. It makes a rapid growth, usually providing emergency ground cover the first
growing season.
7. Its aggressive fibrous root systems bind and hold soils in place that are subject to
critical erosion hazards. Also the organic material provided by this extensive
root system contributes to the physical improvement of the soil. This factor is
important in a conservation cropping system resulting in increased infiltration
(water insoak), more efficient use of fertilizer, and better crop yields. These
facts are well substantiated by many reports of farmers and ranchers using
weeping lovegrass in their conservation cropping system.
8. Forage, surplus to conservation needs, is available for livestock.
9. While reducing soil loss, seed and forage provide food and cover for local
wildlife.
10. Weeping lovegrass makes a significant contribution to environmental improvement. To observe a field of weeping lovegrass waving in the wind is a source of
pleasure to the conservation minded.
Hi Staten (7), an early authority on weeping lovegrass, reported that weeping
lovegrass in Oklahoma is specifically recommended for plantings on abandoned cropland
and protection of water disposal systems.
Dalrymple (2), reporting on soils adaptation, states that weeping lovegrass will
establish and produce well on most well-drained soil types. It does best on, and stabilizes, sandy loam soils. Growth is good on clay loam soils of southeastern Oklahoma and
northeastern Texas. Good stands may be attained on tight exposed subsoils, rocky areas,
coarse sand, and soil with other undesirable characteristics. Soil pH has little influence
on adaptation of weeping lovegrass. It grows well on acid soils of southeastern United
States, on mine spoils with about pH 4, and on high basic soils in south central Oklahoma
when the cause of the basicity is not sodium. In the more arid western areas, weeping
lovegrass grew well on soils of pH 8 and above, but severe chlorosis occurred in
midseason. It grew better in laboratory tests at pH 5 than at pH 6 with growth reduction
at pH 4.5
General conservation uses are discussed as follows:
1. Wind erosion control—Rapid growth on soils subject to wind erosion makes
weeping lovegrass an important forage grass. This use was recognized early in
the evaluation of trial plantings by SCS technicians. Plantings on “blow soils”
should be made in noncompetitive cover. This adds additional insurance for a
good stand and rapid growth.
2. Stabilization of critical silt source areas—For many years, there has been widespread use of weeping lovegrass for silt pollution abatement of state streams and
water storage facilities. Plantings on such areas usually require the use of diversion terraces to control overhead water. Fencing to exclude or control livestock is
essential in the establishment and maintenance of an adequate erosion control
cover on such problem areas.
41
3. Protection of earthen installations—In recent years, the SCS, U.S. Army Corps of
Engineers, State Highway Department, and Defense Department installations
have standards and specifications for using weeping lovegrass for erosion control
purposes on installations such as roadside cuts and fills, dams, spillways, borrow
areas, etc.
Although many favorable factors have been presented, weeping lovegrass should
not be considered as a panacea. Based on many years of personal observations, some
important limitations are listed as follows:
1. Weeping lovegrass is not suitable for areas subject to periodic inundation. It is
known from ARS studies (3) that a well-established stand of weeping lovegrass
does not survive more than a few days (five to seven) of inundation. Neither will
it survive effectively on poorly drained soils.
2. Longevity of the stand is influenced by a number of factors such as a poor soilmoisture relationship. This is probably the major contributing factor to “lumping
out” on areas on top of dunes and ridges; also included are slopes of 25 percent or
steeper. To combat this problem, SCS does not recommend pure plantings of
weeping lovegrass on such critical sites. Weeping lovegrass is mixed with locally
compatible species such as sericea lespedeza in eastern Oklahoma, King Ranch
bluestem in southern Oklahoma, and Caucasian bluestem in northern Oklahoma.
Past performance of weeping lovegrass in Oklahoma has assured for it a future
with a high potential. It is a multipurpose grass furnishing quality forage while controlling erosion under a wide variety of conditions.
42
References
1. Crider, Franklin J. Three introduced lovegrasses for soil conservation. Soil
Conservation Service Cir. No. 730. August 1945.
2. Dalrymple, R. L. Weeping lovegrass management. Bul. Publication, Agricultural
Division, Noble Foundation, Foundation, n.d.
3. Gamble, M. D., and E. C. Rhoades. Effect of shoreline fluctuations on grasses
associated with upstream flood prevention and watershed protection. Soil
Conservation Service, USDA, and the Soil and Water Conservation Research
Division, Agricultural Research Service, USDA, in cooperation with the
Oklahoma Agricultural Experiment Station. Agron. J. Vol. 56:21-23, 1964.
4. Harlan, Jack R., C. E. Denman, and W. C. Elder. Weeping lovegrass. Oklahoma
Agricultural Experiment Station, Oklahoma A & M College. Forage Crops
Leaflet No. 16, February 1953.
5. Staten, H. W. From poverty trail to prosperity highway (excerpt from Weeping
lovegrass in Oklahoma). H. L. Wallis, Certified Seed Grower. December 1946.
6. Staten, H. W. Weeping lovegrass for the Southwest. Crops and Soils Magazine,
American Society of Agronomy, Vol. 2, No. 2, November 1949.
7. Staten, H. W. Weeping lovegrass in Oklahoma. Agronomy Department, Oklahoma
A & M College. October 1943.
8. Staten, H. W., and Harry M. Elwell. Weeping lovegrass in Oklahoma. Oklahoma
Agricultural Experiment Station Bul. No. 281. June 1944.
43
Burning Old Growth of Weeping Lovegrass1
E. H. McIlvain and M. C. Shoop
Agronomist and Range Scientist
Woodward, Oklahoma
Summary
Excessive accumulations of old growth of weeping lovegrass (Eragrostis curvula
[Schrad.] Nees) lower forage production and cattle gains. The old growth must be removed to produce profitable pasture. Burning is often the only practical solution.
Fire research has been conducted on weeping lovegrass at Woodward, Oklahoma,
since 1963. Results show that burning can maintain or increase forage vigor, quality,
productivity, seed production, and beef production. Controlled fire can also reduce
overly thick litter without destroying all of it. Other advantages include removal of dense
tiller stubs, removal of manure that can foul hay, control of plant and animal insects and
diseases, and control of winter annual weeds and grasses. Burning also helps control
injurious spot grazing.
Burning should not be done annually, when soil moisture is so low that spring
growth may not start after the burn, when plants are weak from overgrazing and/or
drought, when some litter is needed on soil between plants, or when accidental fire
danger is high.
The technique of conducting a carefully controlled burn requires knowledge,
experience, planning, patience, proper equipment, and diligent care—but these can all be
learned. Burning can then be used effectively as a pasture management tool.
Introduction
Excessive accumulations of old growth of weeping lovegrass (Eragrostis curvula
[Schrad.] Nees) lower forage production, cattle gains, and profit. The only solution to the
old-growth problem is to remove it. The pertinent question becomes “how,” since the old
growth can be grazed, mowed, or burned.
Grazing, of course, is the best method if it can be done at a profit. Usually,
however, cattle gains are low on old, rank growth of weeping lovegrass (hereafter called
lovegrass) that is very low in digestibility, and cattle usually decline in price per pound as
they become older. Thus, grazing is seldom a practical solution.
1. A progress report based on cooperative studies conducted by the Crops Research Division, Agricultural
Research Service, U.S. Department of Agriculture, and the Oklahoma Agricultural Experiment Station,
Stillwater, Oklahoma.
44
Mowing heavy accumulations of old growth is usually not profitable, because of
the large volume of “old straw” that must be physically removed to prevent choking out
new growth. However, mowing can be an acceptable solution on very small acreages, or
if the “old straw” can be turned to a profit.
Burning is often the only practical solution. Burning has frequently been condemned as a destructive practice that is not compatible with conservation. However,
research on controlled burning of lovegrass has shown that fire can be a useful and
profitable pasture management tool consistent with conservation.
Specific objectives of our fire research have been to determine (1) effects of fire
on forage, seed, and beef production; (2) effects of date of burn; (3) effects of kind of
burn, i.e., backfire, sidefire, or leadfire; (4) effects of wind, humidity, and air temperature;
and (5) effects of volume of standing fuel and volume of detached litter. Our studies are
not yet finished, and we are far from being experts in fire research, but we now have
sufficient information to let us present some conclusions.
The purpose of this paper is to present progress in our burning research and to
discuss our practical experiences in order to encourage the use of burning as a management tool where it is needed and to discourage its use where it is not needed.
Another objective is to describe how to conduct a safe controlled burn.
Methods
Lovegrass burning studies have been conducted on the Southern Plains
Experimental Range near Woodward, Oklahoma, every year since 1963 and are still in
progress. Some studies were conducted in replicated small plots within burned pastures
10 to 25 acres in size. Some studies were conducted in grass nurseries by burning
lovegrass growing as spaced plants, in rows, or in small plots. Other studies were made
by burning small pastures 3 to 12 acres in size. Subsequent forage production was then
measured in comparison with comparable unburned pastures.
Detailed procedures of conducting each study will not be discussed in this brief
report. In general, most burns were made in April, but some were made in March and
May. Most fires were set when conditions were near optimum for obtaining a controlled
burn. These conditions will be discussed later.
At the time of the burn, data were obtained on flame height and rate of spread of
backfire, sidefire, leadfire; on fuel and soil moisture conditions; and on wind, temperature, and humidity.
Frequent observations were then made of the experimental burns to determine (1)
the rapidity, color, and vigor of regrowth; (2) the effects of late frosts after burn; and (3)
the palatability of the forage crop for insects, rabbits, other rodents, and cattle.
45
Forage production was measured by the micro-unit forage inventory technique, by
small-plot mower, or by mowing and baling. Seed production was measured by collecting seeds from individual plants, or sections of row, or by using a combine on small
pastures.
Results
In general, controlled burning disposed of the old, rank growth at a low
cost. This was done without injuring the plants and without causing wind and water
erosion. The end effect was to increase the grazing value of our lovegrass pastures.
Specifically, the effects of controlled burning were
1. A small increase in forage vigor and productivity (Table 1).
Table 1. Summary of forage production on burned and mowed weeping lovegrass1
Forage Production, Lbs./Acre
Year of Burn
Burned
Mowed
1963
1950
2080
1964
2620
2160
1966
2010
2020
Avg.
2190
2090
1
Average of four to ten replications each year. Plots were burned in April and were not
fertilized. Harvests were made in midwinter.
2. A large increase in seed production (Table 2).
Table 2. Summary of seed production on burned, mowed, and untreated weeping
lovegrass, 19661
Seed Production, Lbs./Acre
Variety
Burned
Mowed
Untreated
Morpa
65
45
35
“673”
68
40
30
Avg.
66
42
32
1
Average of eight replications on each of two burning and mowing dates and four fertilizer rates.
46
3. Production of lush, palatable, grazeable forage that was earlier, darker green in color,
and higher in protein content. Burning caused lovegrass to start growth earlier in the
spring and to grow more rapidly. Usually early growth will be an advantage, but it is
possible for early growth to be a disadvantage if it is killed by late-spring frosts. Regrowth following burning in mid-April 1967 was frosted and killed back three times in
late April and early May. The grass still had sufficient root reserves to produce forage a
fourth time and to make good summer growth. Had the plants been weakened by
previous continued overgrazing and/or drought, the early growth combined with frosts
may have been harmful.
4. A reduction in excessively thick litter (mulch or thatch) which can become two or three
inches deep under a mowing program that does not include removal. Thick thatch acts
as a sponge to absorb small showers and release the moisture through evaporation.
Thick thatch also ties up soil nitrogen and other nutrients, and it prevents natural seedling establishment. On the other hand, some litter between the plants is beneficial
because it shades the soil, retards evaporation, promotes water intake, and helps prevent
hoof compaction and topsoil disturbance—all of which affect the lateral surface roots of
lovegrass.
5. A reduction in excessive standing old growth that shades out and crowds out new tillers
and causes “center die-out.”
6. Removal of the excessively thick, several-year accumulation of old dead tillers that also
causes “center die-out.”
7. Removal of manure so that hay can be made without contamination.
8. Some control of plant and animal insects and plant disease organisms.
9. Surprisingly, even small seedlings which started growth in the previous year were
usually not killed.
10. Burning caused the soil surface to become firmer. This may be an advantage or disadvantage, depending on soil conditions.
11. Burning killed winter annual weeds and grasses. Again, this may be an advantage or
disadvantage, depending on the grazing value of the winter annuals.
12. Burning helped control spot grazing that can, and usually does, reduce steer gains 50 to
80 pounds per head during a summer growing season.
13. Burning, a two-edged sword, destroys the stubble barrier (pincushion), a tool that helps
control spot grazing. This barrier must be reestablished each time a pasture is burned.
This is one of the reasons we strongly advise against annual burning.
47
Discussion
Briefly, conditions under which burning is not advisable are
1. Annually
2. When soil moisture is so low that spring growth may not start after the
burn
3. When plants are weak from overgrazing and/or drought
4. When some litter is needed on soil between plants
5. When accidental fire danger is high
In general, burning is usually not needed unless a pasture has an excessive accumulation of (1) forage, (2) litter, or (3) dead tiller stubs.
How to Burn
We decided to close this discussion on burning with the subject “how to burn”
because many people are afraid to use fire as a management tool. This is usually the
result of past sad experience with wildfire. It is true that controlled burning requires
knowledge, experience, planning, patience, good equipment, and great care—but these
can be acquired. Probably some of you in this room have never seen a controlled fire—
nor had we until 1960, when we started fire research on shinnery oak rangeland.
Our background: We were baptized on the use of controlled fire by Mr. Francis
Davison, who operates a 110,000-acre ranch near Arnett, Oklahoma. Mr. Davison’s
father started his controlled-burning experiences in 1902 when he put the ranch together.
Francis Davison cut his eyeteeth while helping his father to burn, but after the “conservation education” which he received in college, he discontinued burning on the ranch from
about 1945 to 1960. During these fifteen years, he gradually became aware of the need
for burning. Mr. Davison’s practical experience has been invaluable to us, and we will
try to pass a little of it on to you.
When to burn: February 15 to April 15, or about one week before the average
date of the last killing frost (Burton, 1969).
Stage of growth: Green growth should be showing. This helps insure that regrowth will be rapid and the land will not be left long without vegetative cover to protect
it against wind and water erosion and the drying effects of the hot sun.
Time of day: It is safest to start fires in the evening about one hour before dark.
As the temperature declines, the humidity usually goes up, the wind usually dies down,
and the danger of accidental fire decreases greatly.
Soil moisture: It is necessary to have enough soil moisture to insure start of green
growth. It would be folly to burn when the top 2 feet of soil are without moisture.
48
Fuel moisture: If a pasture can be burned one, two, or three days after a rain or
shower, the plant base and the soil litter will be damp. Under these conditions and with
the proper conditions of wind, humidity, and temperature, fire can almost literally be used
to “mow” a pasture.
Wind: A steady breeze of five to ten miles per hour is ideal.
Humidity: The danger of accidental fire increases when humidity goes down.
When humidity gets under 30 percent, fire danger is critical.
Temperature: Surprisingly, low air temperature decreases fire intensity greatly. It
is much easier to control a fire when air temperature is 50o F than when it is 70o F or
higher.
Whirlwinds: Whirlwinds can be created when wind velocity is low, the temperature is 70o F or above, and the sun beats down on a burned pasture. The whirlwinds can
set accidental fires, and they must be watched carefully.
Fireguards: It is essential that good fireguards be made before burning starts.
The principle is to remove all fuel down to mineral soil to prevent fire from creeping
across the guard. On lovegrass pastures, we use a weighted grader blade on the back of a
small, three-point-hookup tractor. The front of the blade digs 2 to 3 inches deep, and the
dirt and fuel are cleared from a strip about 3 feet wide. About one day after the fire, we
replace the displaced soil. If grass on the “inside” of the fireguard is tall, the value of the
fireguard can be increased by mowing a strip about 10 feet wide next to the guard. Of
course, the fireguard must completely enclose the pasture to be burned. On large pastures, motor patrols can be used to make a guard 10 to 12 feet wide.
Fire fighters: At least one, two, or three men with shovels and power water
sprayers should be available to “back up” the fire-setting crew. In many rural communities, fire departments have a grass-fire truck that can be rented on a stand-by basis.
Butane torch: A simple, cheap, and very effective torch can be made with a
5-gallon butane bottle, about 6 feet of hose, and 4 feet of thin pipe. The danger of setting
accidental fires is greatly reduced when a continuous line of fire is set (usually from the
back of a pickup) to the fuel just on the inside edge of the fireguard. This torch also can
be used to help widen the backfire area in those cases where the backfire refuses to widen
by itself—and if burning conditions are proper and safe, this is frequently the case.
Power water sprayer: Nearly any livestock sprayer can be used to control the fire
or to stop an accidental breakout. The sprayer should have an adjustable nozzle so that a
fine spray can be used 10 to 20 feet from the operator to control the height of a blaze
along the backfire. The nozzle should be adjustable so that a coarse, direct stream can be
used from 10 to 30 feet away to put out fire.
49
Tractor with grader blade: We always keep our fireguard equipment handy to
establish a new fireguard in the event of a breakout. The man who operates the tractor
also has a shovel available to “back up” the other firefighters.
Backfire, sidefire, or leadfire: Much of our research effort has been spent on
trying to find differences in the effects of backfire, sidefire, or leadfire on the growth of
grass. In brief, our results show little or no difference as to the kind of controlled fire.
Under some conditions, a backfire will burn up more of the plant base and the litter than
will a leadfire. Under other conditions of wind, temperature, and fuel moisture, the
reverse is true. From a practical standpoint, it pays to get a good, wide, safe backfire area
on three sides of a pasture before setting the leadfire. After one has acquired experience,
he can make a judgment as to whether he should allow the backfire to continue to burn
the entire pasture, or whether, from a safety standpoint, he should set a leadfire and finish
the burning job before the wind changes and turns a safe backfire into a dangerous
leadfire.
Weather information: The U.S. Weather Bureau, Oklahoma City, makes a daily
fire-weather forecast and can give you current information on wind velocity, direction,
and expected changes; and on humidity and temperature. A fifty-cent phone call could be
cheap insurance! Similar information, and usually more localized, can be obtained from
FAA flight-service operators at many airports.
Literature Cited
Burton, Glenn W. 1969. Bermudagrass management for the South. Crops and Soils.
22:10-11.
McIlvain, E. H. and C. G. Armstrong. 1966. A summary of fire and forage research on
shinnery oak rangelands. Proceedings Fifth Annual Tall Timbers Fire Ecology
Conference. Tallahassee, Florida.
50
Q.
What is the proper amount of litter to maintain?
A.
About 1/2 inch on the soil surface.
Q.
Are there observations on additional livestock weights due to burning?
A.
None to date.
Q.
In the data of mowing and burning, what was the date of mowing?
A.
The burning and mowing was done on the same date, generally during the first
fifteen days of April at Woodward.
Q.
If you can’t burn early because of a fire hazard, would it be better to put up with the
old litter rather than burn at an improper date?
A.
Generally it would be better to burn. We have burned as late as May 8, burning 6 to
10 inches of green growth in the dry residue without hurting the grass. This destroys some green grass. That pasture, with proper fertility, made 2 pounds per day
average gain on steers. Within three weeks after that burn, there was grazing forage
to last to September 1. If that green and dry residue could be taken as hay, it could
be used as maintenance hay. We have not gotten any advantage to mowing as
opposed to burning on May 8.
51
Research Results on Weeping Lovegrass
Fertilization in North Central Oklahoma
W. E. McMurphy and C. E. Denman
Agronomy Department
Oklahoma State University
Large acreages of weeping lovegrass were planted in the late 1930s and 1940s.
The grass was popular because its seedling vigor made it easy to achieve excellent stands,
it was drought tolerant, and it was productive in the first few years following seeding.
The early optimism about this “wonder” grass of that time rapidly gave way to disenchantment.
After the initial flush of productivity, ranchers quickly found that old weeping
lovegrass fields were producing less than native grass. Furthermore, the cattle did not
like weeping lovegrass, their performance was less than satisfactory, and it often took a
good fence to contain cattle on weeping lovegrass.
Data from this research will help explain the cause of rancher disenchantment
with lovegrass and provide recommendations for its management.
Materials and Methods
The plots were seeded on a Vanoss loam at Perkins, Oklahoma, in June 1964 and
irrigated only in the first year to ensure uniform stand establishment. Fertilizer applications and harvesting began in 1965. The experimental design was a factorial arrangement
of nitrogen and phosphorus in four replications. Fertility treatments were all possible
combinations of nitrogen at 0, 40, 80, and 160 pounds of actual N per acre with phosphorus at 0 and 80 pounds of actual P2O5 per acre, giving eight fertility treatments. Ammonium nitrate and superphosphate were applied in early April each year, but the 160
pounds of N per acre was applied as a split application, the second half being applied in
early July. A uniform application of potassium at 100 pounds of K2O per acre was applied in March 1968 to prevent deficiencies indicated by soil test. The plots were 10 x 25
feet, and forage yields were taken from a 3-x-16-foot area mowed at a 2-inch height.
Forage harvests were made when floral initiation occurred. Thus, weeping lovegrass was
harvested about June 1 and August 1, and the regrowth on all plots was harvested after a
killing frost, except in 1968 when drought prevented any appreciable regrowth.
Results
Nitrogen: Production in plots that received no N degenerated from nearly 4 tons
per acre in 1965 to much less than 1 ton per acre in five years (Table 1). However,
nitrogen fertilized plots which produced 5 to 6 tons per acre in 1965 were producing 3 to
4 tons in 1969.
52
Table 1. Forage Production (Lb./Acre) of Weeping Lovegrass As Affected by Nitrogen
1
and Phosphorus Fertilization at Perkins, Oklahoma
Fertilizer (Lb./A)
N
P2O5
0
0
0
80
1965
7478 e
8177 de
1966
2943 f
2600 f
40
40
0
80
8909 cd
9567 bc
5341 e
5597 de
80
80
0
80
10178 b
10491 b
160
160
0
80
11818 a
12773 a
Year
1967
1856 d
2205 d
1968
894 d
1039 d
1969
1638 d
1411 d
5132 c
5640 c
3083 c
3201 c
3964 c
3998 c
6679 c
7358 bc
7092 b
7825 b
4193 b
5352 a
5813 b
6300 b
8163 ab
8840 a
9373 a
10545 a
4837 ab
5647 ab
6666 b
8118 a
1
Averages within a year followed by the same letter are not significantly different at the
95 percent probability level.
Thus it is not a question of “Should I fertilize with nitrogen,” but instead, the
question is how much nitrogen to use.
Production in 1965, the first year, was high in all treatments because of residual
soil fertility. The site had been in vetch before the grass was planted. A more realistic
response to nitrogen is available in the years 1966–1969 (Fig. 1). The production chart
shows that 80 pounds of N will produce 2 tons of forage per acre by June 1. This also
means that one must stock with enough cattle to utilize 2 tons of growth from late April
to June 15. If this tremendous flush of growth is not grazed off in this short period of
time, the grass matures and becomes stemmy, low in protein, and very low in palatability.
Cattle refuse to eat this more mature forage and will very likely limit their forage intake
to whatever regrowth is available. If the lovegrass growth has not been removed by
grazing, then it should be mowed. It is better to take a hay crop or simply mow it down
for a mulch than to leave this mature forage standing.
One of the management problems with the 80 to 160 N treatments is that 4000
pounds of forage per acre are produced in the first six weeks, but only 2000-2500 pounds
of forage per acre are produced in the next eight-week period (Fig. 1). This calls for a
drastic reduction in stocking rate. Then from August 1 to the end of the growing season
(eight to ten weeks), only 800-1500 pounds forage per acre are produced. Further reductions in stocking rate would be necessary.
53
160N-80 P2O5
7000
-
6000
-
5000
-
4000
-
Forage
Forage
(Lb./A.)
lb./A. 3000
-
2000
-
1000
-
Apr.
80N-80 P2O5
40N-80P2O5
0-0
May
June
July
Aug.
Sept.
Oct.
Figure 1. Accumulated forage production of weeping lovegrass harvested June 1–Aug. 1,
and Dec. 1. Four year average for 1966–1969. The 160 N was a split application with 80
N applied Apr. 15 and July 1.
The growth characteristics of weeping lovegrass, fertilized adequately, suggest
that it would serve as an excellent complementary pasture for native range. Native range
will benefit greatly from any deferment in grazing. The spring deferment of native range
will increase the native grass productivity, and a deferment of weeping lovegrass in late
summer until frost would be beneficial to weeping lovegrass. Both grasses can be used
for winter grazing, and cattle readily graze the weeping lovegrass regrowth during the
winter.
Phosphorus: No appreciable response to phosphorus fertilization has been obtained at the lower levels of production recorded at 40 N or less (Table 1). This means
that the soil phosphorus supply was adequate to support the low level of production. The
response to phosphorus appeared at the higher nitrogen levels (80–160 N). At these
higher levels of forage production, the available supply of soil phosphorus in this study
was inadequate.
The unanswered question is, How much phosphorus is needed? The fertility
treatments in this test were designed to ensure that adequate phosphorus would be available; thus, 80 pounds P2O5 was applied annually. Results from phosphorus studies on tall
fescue and small grains (Elder and Tucker, 1964) and bermudagrass (Elder and Tucker,
1968) indicate that 40 to 60 pounds P2O5 per acre may have been adequate.
54
Potassium: This experiment was not designed to evaluate K (potassium) fertilizer; however, it is known that the K content of forage grasses ranges from one to three
percent (Kilmer et al., 1968). Actual K content of forages depended upon available soil
K and plant maturity. Very young grasses contained as much as 3.5 percent K, but mature
grasses contained about 1.5 percent K.
The forage production for the 160 N-80 P2O5 treatment averaged more than
10,000 pounds per acre the first three years. These levels of forage production could
require 180 pounds potash fertilizer (150 pounds actual K) each year. Soil tests revealed
a soil potash content of medium (170 pounds per acre) in the unfertilized plots, but the
potash content was low (103 pounds per acre) on the 160N-80 P2O5 plots. On the basis of
this test, 100 pounds of potash per acre was applied in the spring of 1968 to help prevent
K from becoming a limiting factor to production.
Crude protein: A good measure of forage quality is crude protein content. In
examining the data of Table 2, one should keep in mind that crude protein of forage is
highest at the initiation of growth and steadily declines as the plant grows. Forage must
have a crude protein content of at least 9 percent to meet the nutritional needs of grazing
cattle (Natl. Res. Council, 1963). Higher protein levels are needed for growth, pregnancy, and milk production.
There is some question if nonnitrogen fertilized forage ever reached the minimum
required level for cattle except at very young stages of growth. This low crude protein
content in the non-N fertilized plots should help explain the poor livestock responses
observed by ranchers many years ago.
When 40 pounds of N per acre was applied, the forage probably had adequate
protein for only a short period of time in the spring. Thus, from the standpoint of both
forage quality and total production, a higher rate of nitrogen fertilization should be
considered.
55
Table 2. Percent Crude Protein in Weeping Lovegrass, Four-Year Average, 1965–1968
N
Fertilizer (Lb./A.)
P2O5
June 1
Harvest Date
Aug. 1
Dec. 1
0
0
6.3 c
4.2 c
2.8 c
0
80
6.2 c
4.2 c
2.8 c
40
0
8.4 b
4.3 c
2.7 c
40
80
8.2 b
4.3 c
2.7 c
80
0
10.6 a
6.3 b
2.7 c
80
80
10.4 a
5.1 bc
2.9 c
160
0
10.6 a
8.2 a
4.1 b
160
80
10.7 a
8.7 a
4.6 a
1
Averages within a harvest date followed by the same letter are not significantly different
at the 95 percent probability level.
At least 80 pounds of N per acre applied in early April was necessary to achieve a
reasonable level of crude protein during the first six weeks. A further application of 80
pounds of N per acre on July 1 helped maintain a nearly adequate minimum crude protein
content in the forage through August 1.
After frost, the dormant forage had a very consistent protein content of slightly
less than 3 percent with a small improvement attributed to the extra eighty pounds of N
(160 N treatment) applied on July 1.
Drought or winterkill: The summer of 1968 was much drier than normal, and
some stand injury was observed only in the 160 N plots in the spring of 1969. This
research was not designed for flexibility in changing N rates. The 80 N (160 N treatment) was applied on July 1 even though drought prevailed. Ranchers should use caution
with summer N applications and not apply excessive N when drought prevails. Phosphorus fertilizer at the 160 N level made no difference in stand survival. Some injury was
observed in all 160 N plots.
56
Recovery of applied nitrogen: The recovery of applied nitrogen in the forage
(Table 3) was computed by
lb. N/acre in
fertilized forage
lb. N/acre in
unfertilized forage
−
lb. N/acre applied as fertilizer
and an example of the calculation for 1965, 40N, 0 P2O5 treatment, is
95 lbs. N/acre in
forage of fertilized plots
−
67 lbs. N/acre in
unfertilized forage
= 71% recovery
40 lb. N/acre applied fertilizer
Table 3. Recovery (in Percent) of Applied Nitrogen from the Forage
Fertilizer (Lb./A.)
N
P2O5
1965
1966
Year
1967
1968
40
40
0
80
71
73
77
97
83
95
66
64
80
80
0
80
67
69
97
93
79
94
65
85
160
160
0
80
43
50
59
67
69
82
45
54
It is noteworthy that in 1966 and 1967, over 90 percent of the applied nitrogen on
the 80N-80P2O5 treatment was recovered in the forage. In 1968, only 85 percent of that
nitrogen was recovered; however, this was the recovery by August 1, because there was
little regrowth due to drought that summer. In 1967, when adequate moisture was available, forage from the 160N-80P2O5 treatment contained 82 percent of 160 N.
Frequency of harvest: The effect of harvest frequency was not evaluated in this
study, but this information is available from earlier research (Denman et al., 1953). A
partial summary of that research is given in Table 4. Clipping more frequently increased
the protein content, decreased the forage yield, and resulted in stand deterioration .
Nitrogen fertilizer with a four-week clipping interval did not harm the stand, although
forage production was only 82 percent of that from six-week clipping intervals.
57
Without N fertilizer, the only way to produce forage with an adequate crude
protein content was to harvest every two weeks, but this treatment killed the grass. Thus,
the current popularity of weeping lovegrass is directly dependent upon fertilizer technology and use.
The P (phosphorus) content of the forage ranged from 0.14–0.22 percent. The P
requirement of cattle is greatest (as high as 0.34 percent of the feed) for actively growing
young steers, and cows in late gestation require almost as much P (Mitchell and McClure,
1937). A cow giving 10 pounds of milk per day requires 0.20 percent P. Phosphorus is
higher in young, rapidly growing tissue than in older tissue and more abundant in leaves
than stems (Sullivan, 1969). Thus, depending upon class of cattle, maturity of plant, and
other factors, it is easily possible for weeping lovegrass to be deficient in P for the grazing animal.
Table 4. The effect of clipping frequency and nitrogen fertilization upon forage production, protein and phosphorus contents, and survival of weeping lovegrass, three-year
1
average
Clipping
Frequency
2 weeks
1
Fertilizer
0
100 N
Forage
(Lb./A.)
2209
4537
%
Protein
10.3
12.2
%
Phosphorus
0.22
0.20
Lovegrass
Survival
Very poor
Poor
3 weeks
0
100 N
3235
5692
8.4
10.0
0.18
0.17
Fair
Good
4 weeks
0
100 N
3335
6693
7.5
8.4
0.18
0.15
Good
Excellent
6 weeks
0
100 N
4186
8199
6.3
7.1
0.15
0.14
Excellent
Excellent
Denman et al., 1953.
Summary
Without nitrogen fertilization, the production of weeping lovegrass drops to very
low levels; and furthermore, the protein of this unfertilized forage is far below the minimum level required by cattle. From the standpoint of both production and protein content, at least 80 pounds of N per acre should be used. In years when precipitation is
adequate, then further additions of N fertilizer would be worthwhile. A definite response
to phosphorus was obtained, and soil tests had indicated possible potassium deficiencies
with the higher levels of production. The importance of N fertilization and “keeping the
plant young” have been established as necessary for producing quality forage for grazing
animals.
58
Literature Cited
American Society of Agronomy. 1968. The role of potassium in agriculture. Edited by
V. J. Kilmer, S. E. Younts, and N. C. Brady. 509 pp.
Denman, C. E., and V. G. Heller. 1953. Performance of weeping lovegrass under different management practices. Okla. Agr. Exp. Sta. Tech. Bul. 48.
Elder, W. C., and B. B. Tucker. 1964. Pasture management, grazing studies, and forage
crop fertility tests. Okla. Agr. Expt. Sta. Proc. Series 475.
Elder, W. C., and B. B. Tucker. 1968. Pasture management, biennial report of progress
for 1966 and 1967 on forage crop grazing studies and fertility tests. Okla. Agr. Exp.
Sta. Proc. Series 583.
Mitchell, H. H., and F. J. McClure. 1937. Mineral nutrition of farm animals. Nat. Res.
Council Bul. 99.
National Research Council. 1963. Nutrient requirements of beef cattle. Natl. Res.
Council Publ. 1137.
Sullivan, J. T. 1970. Chemical composition of forages with reference to the needs of the
grazing animal. U.S. Dept. Agr. ARS 34-107.
Q.
How do you get phosphorus into established stands without damaging them?
A.
This was broadcast on the soil surface.
Q.
Doesn’t it need placed into the soil?
A.
We are getting responses with broadcast application.
Q.
Why?
A.
You do increase the efficiency of phosphate fertilizer if it is worked into the soil.
This is the reason Mr. Dalrymple stressed the need for soil testing prior to planting.
This would allow preplant applications. Because there is no good way to place it
into the soil, you still get responses from topdressed phosphate. McIlvain said the
roots of weeping lovegrass include a mass of roots immediately below the surface.
This probably helps in phosphate uptake.
59
Q.
Can we use tissue analysis under high fertilization to evaluate the fertilization
program?
A.
We haven’t done this.
Q.
What degree of phosphorus and potassium would you like to have in the plant?
A.
About 0.35 percent potassium to supply animal needs. About 0.20 percent phosphorus for a wintering cow, up to 0.35 percent for late pregnancy.
Q.
Would it be easy to get the potassium level suitable, but difficult to attain those
levels of phosphate?
A.
Weeping lovegrass is generally adequate in phosphorus during the growing season,
but deficient during dormancy. Protein supplements will generally supply phosphorus to fill the deficiency.
60
Fertilizing Weeping Lovegrass in Western Oklahoma1
Woodward, Oklahoma
Summary
Fertilizer studies conducted on Pratt loamy sand near Woodward, Oklahoma,
since 1947 have shown that nitrogen fertilization is essential for making high profits on
weeping lovegrass (Eragrostis curvula [Schrad.] Nees). Although we have been unable
to measure any significant plant response to applications of phosphorus, potassium,
calcium, sulfur, magnesium, and the trace minerals, soil known to be deficient in one or
more of these nutrients should probably be fertilized to meet requirements as shown by a
good soil test.
Our fertilizer studies were conducted on replicated small plots and grazed pastures. Results presented in this progress report are only indicative of nitrogen (N) responses because early results were obtained on mismanaged lovegrass, in drought years,
and with urea rather than with ammonium nitrate; and insects, rabbits, and rodents grazed
the fertilized plots heavily at times. We feel the following results are conservative,
probably relative, and indicative:
1. Forage yield is increased about 50 percent with 30 pounds N and 100 percent with
60 pounds N, but the 60 N rate is not recommended as a single application.
2. A four-year grazing trial showed that a single application in April of 35 pounds N
per acre increased yearlong steer gains 10 percent, carrying capacity 25 percent,
beef production per acre 31 percent, and profit per acre 36 percent.
3. Protein content of forage was increased by N fertilization.
4. N-fertilized lovegrass was always much more palatable.
5. N-fertilized lovegrass stayed green longer into drought periods and regrew faster
following clipping or grazing.
6. N fertilization increased seed production.
7. Ammonium nitrate produced 21 percent more forage in 1969 than did urea.
Oklahoma.
61
8. The safest and most economical rate of N is about 30 pounds in each of three
applications, about April 1, June 1, and August 1 if soil moisture is present and if
previously applied N has been “used.”
9. N available for plant growth on grazed pastures after three or four years of fertilizer treatment may be 50 percent more than the annual application rate due to
“recycling” through the grazing animal.
10. Because “recycling” cannot occur on hay fields, it is suggested that 40 pounds N
be used for each application.
11. N is an excellent tool to help control spot grazing.
Introduction
Nitrogen fertilization of weeping lovegrass (Eragrostis curvula [Schrad.] Nees) is
essential for high profits. This statement has been found to be true by every investigator
and every livestock producer. The pertinent question is not whether nitrogen is needed,
but how much, what kind, when, and how often.
The purpose of this paper is to present results of several fertilizer studies on the
effects of applying nitrogen and other fertilizer nutrients to weeping lovegrass grown for
pasture and hay. Specific objectives of our studies were to determine (1) effects of date,
rate, and kind of nitrogen; (2) effects of single vs. multiple applications; and (3) effects of
rate and kind of other fertilizer nutrients on forage yield, quality, hardiness, and beefproducing value.
Methods
Our first grazing studies with nitrogen on weeping lovegrass (hereafter called
lovegrass) were conducted in 1947 and 1948. Small-plot studies were also conducted in
1947. Other grazing and small-plot studies have been conducted annually since 1963.
Most of our studies were conducted on the Southern Plains Experimental Range
near Woodward, Oklahoma. Predominant soil types are Tivoli dune and Pratt loamy fine
sand, and Pratt fine sandy loam. The soils are deep single-grain sands deposited by wind
and water. Water-intake rate is rapid, and water-holding capacity is low—about 1 inch
per foot of soil. Soil pH averages about 6.0; organic matter is low—about 1 percent in
the top foot; available phosphorus and potassium ranks medium high in tests; and the
soils below 40 inches are high in calcium.
Average annual precipitation is 23 inches, with extremes of 10 and 43 inches, and
the growing season (Apr.–Sept.) precipitation averages 16 inches, with extremes of 8 and
30 inches.
62
Lovegrass pastures used for the grazing studies varied from 6 to 25 acres in size.
Each treatment was applied in two to four replications. Small plots varied in size from 5’
x 12’ to 12’ x 87’. Experimental design was usually a randomized block with two to
eight replications.
The nitrogen fertilizer (prilled pellets) was topdressed on pastures with a Gandytype spreader or “whirlwind” spreader. Nitrogen was applied to small plots either with a
Gandy-type spreader or a hand-held “cyclone” spreader using light aluminum shields to
prevent contamination of adjacent plots. Border areas were fertilized on all small plots.
Source of nitrogen was either ammonium nitrate with 33.5 percent nitrogen or
urea with 45 percent nitrogen. Rates of nitrogen used in this report are all expressed as
pounds of actual nitrogen (N) per acre. Fertilizer was usually applied about May 1,
except in date studies.
Results and Discussion
Results presented in this progress report are only indicative of N responses
because many of our early results were obtained on mismanaged lovegrass. It was not
until 1969 that several essential principles of management became clear to us; i.e., grazing or cutting at forty-day intervals, grazing or cutting to a 4-inch stubble, and
topdressing with small, frequent applications of N. Even then, our studies were not
conducted on pastures and plots with several successive years of treatment—a factor we
now consider essential. In addition, we found ammonium nitrate was, at least in some
years, considerably more effective than urea, as will be discussed later, and several of our
studies were made with urea. Also, precipitation was below average in six out of the past
seven years. Precipitation during the seven years was only 82 percent of average. Furthermore, insects, rabbits, and rodents seek and eat the more palatable forage on fertilized
small plots that are surrounded by unfertilized areas. Because of these many disturbing
factors, our fertilizer responses are probably quite conservative, but we feel they are
probably relative and indicative.
Yields: Forage production was usually increased about 50 percent from a single
application of 30 pounds of N (Table 1). Production was usually doubled by a single
application of 60 pounds of N—but this rate, as a single application, is not recommended
because it can cause summer die-out (even on fine-textured sands) during short, severe
drought periods. On fine-textured loam, silt, or clay soils, 60 pounds of N has caused
catastrophic die-out during drought.
63
Table 1. Summary of Effects of Fertilizers on Forage Production of Weeping Lovegrass, 1963–69
Fertilizer
Rate/Acre
N
P
K
0 -0 -0
30 -0 -0
60 -0 -0
90 -0 -0
120 -0 -0
160 -0 -0
320 -0 -0
30 -30 -0
30 -30 -30
160 -40 -40
Rainfall,
Apr–Sept5
1962
4020
—
—
—
—
—
—
—
—
—
1963
2010
3080
4420
—
—
—
—
2920
2630
—
21.912.9
Yearly Forage Production, Lbs. per Acre
1964 1965 1966 19661 19672 19683
2840 3340 2520 1390 1430
920
4350 4080 —
1730 1840 1750
—
—
3770 —
—
2230
—
—
—
1850 2040 1770
—
—
3790 —
—
1820
—
—
—
2140 3020 1860
—
—
—
1880 2550 —
—
—
—
—
—
—
—
—
—
—
—
1920
—
—
—
1880 2610 —
12.5
13.1
9.5
9.5
19.2
14.6
13.9
19694
1760
—
3460
4480
—
—
—
—
—
—
19694
1350
2300
2730
—
—
—
—
—
—
—
13.9
1
Surprisingly, die-out on 160 N and 320 N plots was only about 20 and 35 percent,
respectively.
2
Repeat harvest of 1966 treatments.
3
Fertilized 6-24-68 after one unfertilized crop was harvested. Yields were measured on 93-68 after droughty growth in July and Aug.
4
Two cuttings only. Last crop was eaten by armyworms.
5
30-year avg. for April–Sept. is 16.6 inches.
Steer gains: Results of a four-year grazing trial comparing no N with 35 pounds
of N showed that nitrogen increased forage production about 40 percent, steer gains 10
percent, carrying capacity 25 percent, beef production per acre 31 percent, and profit per
acre 36 percent.
We emphasize that these rather small but significant percentage increases are from
a single yearly application of 35 pounds of N from urea. We now know that topdressed N
from urea can be less effective than N from ammonium nitrate.
Chemical composition: Ammonium nitrate was broadcast on small plots at 0, 30,
60, and 90 pounds N per acre on May 18, 1947. Samples of forage harvested on July 29,
August 13, and September 18, 1947, were sent to Oklahoma State University for a standard proximate analysis. Precipitation from July 1 through October was only 2.8 inches,
whereas average for the four months is 9.2 inches.
Protein content of the grass increased as the rate of N increased up to 90
pounds—but, again, we now know that rates as high as 60 to 90 pounds in a single
application can cause summer die-out. Phosphorus content did not appear to be altered
64
by application of nitrogen. Calcium, ash, and fat content were decreased about 10 percent, whereas crude 10 protein, nitrogen-free extract, and carotene (vitamin A) were not
changed.
Other investigators also found that protein content is increased by nitrogen fertilization (Dalrymple, 1969; Streetman, 1966; Denman, et al., 1953; Lesch and Oosthuizen,
1965).
Color and palatability: Within three or four days after a rain, which follows
application of N, lovegrass foliage turns dark green in contrast to the yellow-green
(almost chartreuse) appearance of unfertilized lovegrass on typical low-fertility soil. The
leaves of N-fertilized plants grow wider and “softer” than leaves on unfertilized plants.
Nitrogen-fertilized grass is selected avidly by all classes of livestock. Steers that
grazed on fertilized plots in a “cafeteria” consumed the forage on plots fertilized with 90
pounds of N first, the 60 N plots second, and the 30 N plots third, and only after the
fertilized forage was consumed did they browse the unfertilized plots.
The preference of cattle for N-fertilized lovegrass lasts summer-long and even
into winter when all grass is dormant. In fact, steers have eaten spot-fertilized, summerdormant grass in preference to unfertilized green grass.
Growth during drought: Nitrogen fertilized lovegrass usually stayed green further
into a drought than did unfertilized grass. In some drought years, fertilized grass did not
turn brown at all, whereas unfertilized grass became quite summer dormant. We feel this
response was caused by the more vigorous root growth made by fertilized plants. However, a word of caution is needed here. Fertilized lovegrass must be clipped at about
forty days of age during a drought to prevent excessive growth, transpiration of water,
and die-out.
Nitrogen-fertilized lovegrass also regrows faster after being grazed or mowed
than does unfertilized lovegrass.
Seed production: Nitrogen fertilization increased heading, seed set, and seed
production (Harlan et al., 1953).
Use ammonium nitrate: During 1969, ammonium nitrate produced 21 percent
more lovegrass forage than did urea (Table 2). Burton (1969) found that urea topdressed
on pastures can be as efficient as ammonium nitrate if applied immediately after a burn.
We have had no experience with N as a liquid or as a gas.
65
Table 2. Summary of weeping lovegrass forage yields in 1969 as influenced by date,
rate, and kind of nitrogen1
Nitrogen
Lb./A, Source2
80, urea
40, urea
Date of Application
Sept 16, 19683 March 18, 1969 May 16, 1969
Lbs dry matter per acre
Avg.
2600
2200
2400
2900
2400
2650
2100
2100
2100
2500
2200
2350
18
21
0
14
Avg.
3400
2700
3050
3200
2700
2950
2700
2300
2500
3150
2600
2850
Increase 80 over
40, %
26
18
17
21
Increase of AN
over urea, %
27
11
19
21
Avg.
Increase 80 over
40, %4
80, AN
40, AN
1
Study was conducted with six replications. Plots were 12’ x 87’ in size. First cutting
June 2, 1969; second cutting July 14, 1969; a third cutting was eaten by armyworms in
September and October.
2
The 45 percent urea and 33.5 percent ammonium nitrate were broadcast on soil surface.
3
Nitrogen applied September 16, 1968, changed grass color to a dark green, and foliage
appeared to grow more, but dry matter yields on February 12, 1969, showed no increase
due to September nitrogen.
4
Average yield of unfertilized plots harvested on similar dates was 1350 pounds per acre.
Rate of nitrogen: The safest and most economical rate of N is about 30 pounds
for each application. In northwestern Oklahoma, apply N about April 1, again on June 1,
and again on August 1, if the subsoil has at least 1 to 2 feet of moisture at about those
dates and if the previously applied N has been “used.” In a dry year, only 30 pounds of N
may be necessary. In other years, apply either 60 or 90 pounds split into two or three
applications, depending upon rainfall. Again, rates higher than these can cause die-out
during severe dry spells.
66
In the 30- to 50-inch rainfall areas of Oklahoma, rates of 150–200 pounds actual
nitrogen per acre (in split applications of about 50 pounds of N) are satisfactory
(Dalrymple, 1969).
As a general principle, it will pay to be on the low side of the optimum rate of N
because of drought. The rate of N application to lovegrass in western Oklahoma must be
related to current and expected precipitation rather than to genetic potential of the grass to
use N. We have applied up to 300 pounds of N on lovegrass without injury in some years
but in other years, a single application of 60 pounds of N has caused disastrous die-out.
Again, the principle of using small frequent applications appears to be the wise course.
Single vs. multiple applications of nitrogen: Nearly all of our N studies have been
made with single applications. Results obtained in 1969 proved conclusively that small
frequent applications were much safer, more efficient, and profitable than single applications.
The key to applying small frequent applications seems to be to fertilize for each
crop. Normally, in northwestern Oklahoma, we can make three harvests, either by grazing or by mowing. The dates of harvest, of course, vary a little from year to year, but
they normally come about May 25, July 5, and August 15.
After only a little experience, a grower can “judge” whether or not the previous
application of N has been “used up.” This seems to be an important key in the decisionmaking process. If only a small forage crop is harvested after forty days of dry weather,
it is probable that N need not be reapplied, particularly if the pasture or field has been
properly fertilized for the past several years.
Recycling of nitrogen through the grazing animal: R. L. Davidson (1964), working in South Africa, has shown that about 80 percent of the N consumed by a steer is put
back on the pasture in the form of urine and manure. He stated that about 25 percent of
the returned N becomes available the first year and another 25 percent is available in the
second year. If this be true, and observations in our pastures seem to confirm the findings, the N available for plant growth after three or four years of fertilization is about 50
percent higher than the actual application rate (Table 3).
Nitrogen rate for hay production: In view of the information just presented on
“recycling of N through the grazing animal,” we feel that small, frequent applications of
40 pounds of N may be more effective than 30-pound applications when all forage
produced (except aftermath) will be hauled from the field.
67
Table 3. Fertilizer and Excretal Nitrogen Available for Plant Growth Due to Recycling of
Nitrogen through the Grazing Animal
Source
First
Applied N
80% x 25% (1st yr.)
80% x 25% (2nd yr.)
30
—
—
Totals
Applied N
80% x 25% (1st yr.)
80% x 25% (2nd yr.)
Totals
30
90
—
—
90
Nitrogen, Lb./Acre
Year
Second
Third
Fourth
A. 30 pounds N applied annually
30
30
30
6
6
6
—
71
92
36
43
45
B. 90 pounds N applied annually
90
90
90
18
18
18
—
22
26
108
130
134
Fifth
30
6
9
45
90
18
27
135
1
36 lbs. x 80% x 25% = 7.
43 lbs. x 80% x 25% = 9.
2
Phosphorus, potassium, calcium, sulfur, magnesium, and trace minerals: A total
of thirty-six fertilizer treatments were applied to replicated small plots of lovegrass in
1968. Typical responses were obtained with the N applications, but we could not measure any significant response with phosphorus, potassium, calcium, sulfur, magnesium,
and the individual trace minerals. Phosphorus and potassium were each applied at 30, 60,
and 90 pounds per acre. Calcium was applied at 500 pounds, sulfur at 10 pounds, and
magnesium at 5 pounds per acre.
Nevertheless, soils known to be deficient in one or more of these nutrients should
probably be fertilized to meet requirements as shown by a good soil test.
To date, on Pratt soils, we have never observed a significant change in yield,
color, or palatability of lovegrass as a result of applying nutrients other than N. Our
study of all soil nutrients will continue because the high forage production of lovegrass
may cause deficiencies within a few years.
Lovegrass growing on high-lime soils (Woodward, Quinlan, Vernon, Enterprise)
occasionally shows typical symptoms of iron chlorosis. Applications of polyphosphate
68
fertilizer at 30 pounds P2O5 per acre dramatically corrected the condition in one instance
(verbal communication with Ferris P. Allgood, soil scientist, Soil Conservation Service).
Whirlwind spreaders: The whirlwind fertilizer spreaders available through many
fertilizer dealers are efficient. We get the most uniform application (and the least spot
grazing) when we use a 30-foot swath even if the spreader is rated at a 35- or 40-foot
swath. Some large spreaders are rated at a 60- to 70-foot swath.
Spreader trails: If flags or other travel guides are not used, fertilizer applications
will be streaked, and this will cause spot grazing. A new technique is to make spreader
trails. Flag the pasture at 30-foot intervals (or wider) and use a single 12-inch sweep on a
three-point hook-up. Sweep about 2 inches deep to kill the grass for about 10 feet, then
lift out for 10 feet. On steep slopes, make shorter killed strips. These skip-strips will be
visible for several years, and they do not reduce forage production.
Spot fertilization: Nitrogen is an excellent tool to help control spot grazing.
Apply about 20 pounds of additional N to ungrazed areas. Good judgment and experience are necessary to use this tool at optimum efficiency.
Additional N (about 20 pounds) can also be used on low-fertility areas within a
pasture to obtain higher and more uniform forage production. Nutrients other than
nitrogen may also be helpful on these “poor” sites.
Literature Cited
Burton, Glenn W. 1969. Bermudagrass management for the South. Crops and Soils.
22:10-11.
Dalrymple, R. L. 1969. Weeping lovegrass management. The Noble Foundation,
Ardmore, Oklahoma. 39 p.
Davidson, R. L. 1964. Theoretical aspects of nitrogen economy in grazing experiments.
J. Brit. Grassl. Soc. 19:273-280.
Denman, C. E., W. C. Elder, and V. G. Heller. 1953. Performance of weeping lovegrass
under different management practices. Okla. Agr. Exp. Sta. Tech. Bull. No. T-48.
18 p.
Harlan, J. R., C. E. Denman, and W. C. Elder. 1953. Weeping lovegrass. Okla. Agr.
Exp. Sta. Leaflet No. 16. 4 p.
Lesch, S. F. and S. A. Oosthuizen. 1965. Why Eragrostis curvula is so popular. Farming
in South Africa. 41:20-21.
69
Streetman, L. J. 1966. Ermelo lovegrass. Texas Research Foundation Bull. 25. Renner,
Texas. 15 p.
Q. You did not get response from phosphorus and potassium; what did the soil analysis
show?
A. In general, medium to high levels. You might wish to apply a check strip of your
own.
Q. Have you used anhydrous ammonia for a nitrogen source?
A. No, we have used only pellets. Anhydrous application may destroy some weeping
lovegrass plants, but this may not hurt.
Q. What is the present cost of these materials?
A. About 3¢ per pound actual nitrogen from anhydrous and 7¢ per pound actual nitrogen
from pellets.
Q. What kind of livestock would you recommend for weeping lovegrass?
A. If you grow your forage correctly, it is top quality feed for any kind of cattle.
Q. How do you know when 30 pounds per acre of nitrogen has been used up?
A. You will be able to tell this in one summer’s experience. If you grow 1000 to 2000
pounds of forage on 30 pounds of nitrogen, it will be well used. This is the drier
western region such as around Woodward, Oklahoma. If you live east of these higher
rates, nitrogen rates may be in order. The nitrogen will be used in one bountiful crop.
If regrowth is chartreuse in color, nitrogen has been used.
70
Weeping Lovegrass in Integrated Forage Systems
Noble Foundation
Ardmore, Oklahoma
An integrated forage system is the combined use of two or more forages. The use,
and possible use, of weeping lovegrass in these programs is the essence of this report.
Many forages can perform better if used in an integrated program. Weeping lovegrass is
not an exception. Some of the most unsatisfactory production and unfair evaluation
comes from yearlong, full-summer, or other multiseason grazing programs.
Why integrate: There are numerous possible advantages to using an integrated
forage program. Among the more important ones are (1) increased total yields per
pasture or per unit; (2) better green forage distribution—yearlong if possible; (3) maintenance and proration of higher quality forage; (4) integration allows a forage to be used at
its season, when it is ready, while another forage readies itself for its season; thus, each
can be used at their best and most productive periods; (5) better average daily gain or
maintenance of livestock; and (6) integration allows different species utilization to be
timed for regrowth and recuperation.
Weeping Lovegrass Season: A vital part of using any forage in an integrated
program is knowledge of the season of growth, how much it can produce, and the general
variability and control of quality. With this knowledge, any forage can be judged as to its
actual and potential worth in a given forage program.
For general comparison, the season of weeping lovegrass can be related to other
forages. Its green forage available for proper grazing is regularly three to six weeks
ahead of Midland and Coastal bermudagrass, native range, King Ranch bluestem, and
other warm-season perennial grasses. At Ardmore, it has produced 3,000 pounds per acre
of oven dry forage before bermudagrass was available for any grazing. This is over 100
animal unit days of grazing per acre before bermudagrass is ready. Likewise, it is green
much longer in the fall and winter. Near Ardmore, it has been 50 percent green, by field
weight basis, at Christmastime. It is important to realize that all of these characteristics
must be managed for by timely and proper spring burning, fertilization, and grazing. Any
forage can be managed to maximize desirable characteristics.
In central and southern Oklahoma, weeping lovegrass makes 50 percent to 80
percent of its production by late June to early July. Thus, it is wise to use the grass
heavily during this period.
Generally, weeping lovegrass is very good quality the first six to ten weeks of
growth. During midsummer, quality may decline lower than that of other common
perennials. It will be above these other grasses during fall and early winter. Numerous
management facets can alter these trends.
71
Use With Other Perennials: In the integrated perennial warm-season grass program, weeping lovegrass can be the first to be grazed. After grazing it for several weeks,
other grasses become properly available. For a period, these other summer perennials
can be grazed, allowing weeping lovegrass to regrow. After regrowth, the weeping
lovegrass can be periodically regrazed along with the other forages, or it may be harvested for hay or deferred for fall and winter use.
During 1969, steers from weeping lovegrass were rotated to Midland
bermudagrass during mid-June to mid-July and gained 1.03 pounds as opposed to 0.07
pound from those carried on weeping lovegrass. During the last two weeks in July, these
steers and others on weeping lovegrass gained essentially the same at 0.40 pound and
0.50 pound per day while those on continuous bermudagrass lost 0.13 pound per day. It
was also noted that average gains on early weeping lovegrass, bermudagrass, and King
Ranch bluestem were over 2.00 pounds per day. Gains on midsummer King Ranch
bluestem were about 1.80 pounds per day. With the variation in “best” season, high gains
could be held longer by using an integrated program.
Utilization during fall-winter greenness is important as a termination of summer
grazing programs and/or a beginning to winter green forage programs. However, during
this last eight to twelve weeks of summer before growth terminates, it is wise to defer
intensive use to insure good production the next spring. This is apparently very important in the northern adaptation regions where intensive, short, fall mowing results in
severe winterkill of stands (3). In central to southern Oklahoma, moderate use (to leave a
6-inch stubble) during the fall green period has not produced these or other noticeable
detrimental effects. However, extremely short utilization before, to shortly after, dormancy would be unwise.
Weeping lovegrass is one improved pasture grass that can be used to a great
advantage with native range. The weeping lovegrass can be heavily grazed during its
early growth, allowing native grasses to make growth. If native grass stands are somewhat infested with annual grasses, these grasses should be grazed or controlled to allow
the native perennials to produce. After an early grazing period on weeping lovegrass,
native range can be grazed, or it may be deferred totally until fall. Often some grazing
rotation from weeping lovegrass to native or vice versa is necessary during summer. The
actual amount of weeping lovegrass needed depends on many variables. Around 20
percent of the total pasture acreage in weeping lovegrass has done well. With this type of
system, native grass condition and production can be greatly increased. The same basic
rotation-deferred grazing program of weeping lovegrass works with bermudagrass and
other grasses. In the case of bermudagrass, the ratio of weeping lovegrass to
bermudagrass can be raised to 50:50.
Weeping lovegrass has not been extensively used with cool-season perennials
such as Kentucky fescue, smooth bromegrass, orchardgrass, hardingrass, and others.
However, it can fit into these grass programs in certain areas by being green after their
summer dormancy has begun and before it is broken. Weeping lovegrass may be grown
on different types of soil (upland) less suited to some of the cool-season grasses and thus
72
help to better the overall system. Its total forage production would likely exceed some of
the cool-season grasses. It is quite possible that the cool-season grasses could be used as
a protein supplement for cows, while the weeping lovegrass serves as a roughage during
winter. This could be done by alternately grazing the pastures to limit intake of green
cool-season forage.
Companion legumes: Where legumes are adapted, they have grown acceptably
with weeping lovegrass. Those that have produced much spring and early summer
growth include vetch, crimson clover, button clover, hop clover, sweet clover, white
clover, bur clover, arrowleaf clover, serecia lespedeza, and alfalfa. Legumes that have
produced summer forage in weeping lovegrass stands include alfalfa, serecia lespedeza,
and Korean lespedeza.
Any of these legumes help to make a beautiful pasture, and those that contribute
to better quality during late spring and summer may help keep annual gains high, but
their true value has not been ascertained. The spring annual types prohibit the use of
grass residue burning which is often very desirable. It is doubtful that their presence in
an intensive grazing program would often be more beneficial than burning and nitrogen
topdressing. Under low utilization to allow legume forage accumulation, good visual
nitrogen response from the legume has been noted, but it appears no better or cheaper
than commercial nitrogen. Under heavy legume grazing, there is much less nitrogen
response.
Gains on legumes may be much less than on good, high quality, early weeping
lovegrass. Results of two years and three groups of cattle on early weeping lovegrass and
vetch overseeded in bermudagrass and King Ranch bluestem near Ardmore, Oklahoma,
are given in Table 1. All groups received the same pretreatment to these pastures. This
data is from about the first six weeks of weeping lovegrass and vetch growth. By the end
of this period, cattle have largely begun to graze the grass in pastures overseeded with
vetch. Green forage from vetch and well managed weeping lovegrass becomes properly
available at the same period.
Table 1. Average Daily Gain of Cattle on Early Weeping Lovegrass and Overseeded
Hairy Vetch
1968
1969
Overall
Pasture
Heifers
New Steers
Winter Pasture Steers Average
Weeping lovegrass
3.17
2.29
2.29
2.58
Vetch
1.81
1.46
1.00
1.42
A possible reason for the lower vetch gains is on the basis of nutrient intake
(Table 2). On an equal fill basis, less dry matter and protein are consumed from vetch. It
is very possible that less total weight is consumed from vetch, making the difference
greater.
73
Table 2. Difference in Possible Steer Intake from Weeping Lovegrass and Hairy Vetch,
1969
Forage
Weeping lovegrass
Vetch
Date
4-9
4-9
% D. M.
33
20
% Prot.
19.8
27.8
Lb./25 Lb. of Ingestion
D. M.
Prot.
8.2
1.6
5.0
1.4
In addition to daily gain, the weeping lovegrass has been able to carry two to three
times the stocking rate to result in about five times the beef production per acre for the
same period. Both pastures could have yielded more production through heavier stocking
to May 16, but the relationship of weeping lovegrass to vetch would have been as wide or
wider. These same relationships have been evident in other pastures. During 1969,
weeping lovegrass produced 277 pounds of beef per acre and 118 grazing days per acre
while the best vetch pasture produced a maximum of 55 pounds of beef per acre and fifty
grazing days per acre. As one producer said, “They walk by, lick at it, and it’s gone.”
Another recalled, “It’s like cotton candy, lots to look at—but not much there.” This is
likely true of some other legumes.
Vetch has been dropped as an overseeded, intensively managed, forage crop in
permanent pastures in preference to forage varieties of rye, wheat, and oats. These small
grain forages, overseeded in permanent pasture, can produce in excess of 200 grazing
days per acre and over 400 pounds of beef per acre. Most of this production can be made
before weeping lovegrass regrows or just as it makes spring growth. Vetch has not been
erased as an important conservation and nitrogen supplying legume under moderate
management to allow forage accumulation. During 1969-70, Agent wheat and hairy
vetch were overseeded in the bermuda and King Ranch bluestem. The wheat performed
well; the vetch was practically worthless. Average gain from steers on this pasture during
February to May was 2.39 pounds per day. Plans for the future include more small grain
overseeding in weeping lovegrass and other permanent pastures.
Alfalfa has been of interest as a potential forage quality improvement during
summer, but little grazing has been done. Known weeping lovegrass-alfalfa mixtures
have persisted satisfactorily for four to five years, but have been used primarily for
conservation, hay, and fall-winter grazing.
Weeping Lovegrass—Other Perennial Grass Mixtures: It is normally considered
best to maintain different species of pastures separately. This permits individual species
management with easier control of fertilizer applications and utilization programs. However, there are cases where mixtures seem beneficial.
Grass mixtures are being used where separate maintenance and good rotation
systems are impractical. The merit of these mixtures can be realized by remembering the
green season and other characteristics previously discussed. As an example, many
producers have found they have too much bermudagrass, or too much weeping lovegrass,
74
and have established a mixture to compensate for the one species hang-up. No known
data on carrying capacity, animal gain, etc., is available on the mixture pastures compared
to pure stands. However, it is probable that they are as good as or better than single
species in pure stands.
Weeping lovegrass has been established in thick bermudagrass by planting on a
prepared seedbed. Heavy disking or moldboard plowing of the bermudagrass followed
by firming-packing operations have resulted in good seedbeds. The weeping lovegrass is
planted immediately on the fresh seedbed during the first month of the weeping lovegrass
planting season. Precipitation induces rapid weeping lovegrass emergence to allow it to
establish before bermudagrass causes severe competition. Plowing the bermudagrass 8 to
10 inches deep just before weeping lovegrass planting has been better than disking since
the seedbed is cleaner, and the bermudagrass reestablishes more slowly. The seedbed
must be firmed. In cases where bermudagrass has recovered before weeping lovegrass
emergence, thin weeping lovegrass stands or failure has resulted. The weeping lovegrass
grows much more rapidly the second year and will contribute much forage. Attempts at
direct interseeding of weeping lovegrass have failed due to dry weather.
Bermudagrass has been established in weeping lovegrass by direct sprigging in
weeping lovegrass. After initial establishment, the bermudagrass continues to spread
between the weeping lovegrass clumps.
Bermudagrass–weeping lovegrass mixtures can be easily established by sprigging
bermudagrass and immediately planting weeping lovegrass on the fresh soil.
Mixtures of this type (weeping lovegrass–bermudagrass) appear very promising.
Some have been maintained on farms for years. It appears that timing nitrogen
applications for both species and allowing for periodic regrowth, the stands can be well
maintained for long periods of time.
Other grasses in mixtures involving weeping lovegrass include King Ranch
bluestem, native grass, caucasian bluestem, and Kentucky fescue. More information on
weeping lovegrass–caucasian pasture can be obtained from the USDA (3).
It is occasionally necessary or desirable to plant different species of grasses in
pure stands in the same pasture, but in separate areas. This is, in effect, a mixture since
they are not separately fenced; however, they can be individually treated. The success of
this depends on many management variables. If the acreage portion of each is not greatly
overbalanced, timely nitrogen topdressing and stocking rate fluctuations will result in
good use of the entire area. Weeping lovegrass is often planted in pure stands in native
range and bermudagrass pastures. Cattle will usually graze weeping lovegrass first in the
spring, rotate to bermudagrass or native grass during summer, then back to weeping
lovegrass during fall and winter. Good weeping lovegrass management is necessary to
make this system work at its best.
Small grain overseeding in weeping lovegrass: There is presently enough management knowledge on weeping lovegrass to suffice for weeping lovegrass produc
75
tion alone. Many things are yet to be learned, and one of them is the use of overseeding
weeping lovegrass with winter small grains. These crops would supply green forage at a
time that the weeping lovegrass is dormant. The small grain winter pasture could be very
important in making the weeping lovegrass pasture more valuable.
Bonel or Elbon rye seems to be well suited for this practice. These ryes terminate
production as weeping lovegrass begins production and would be less competitive during
spring than oats, wheat, or barley. Oats and annual ryegrass have been limitedly used. A
weeping lovegrass pasture overseeded with Elbon rye was observed during the 1969–70
winter season near Ardmore, Oklahoma. The rye was drilled in weeping lovegrass in
10-inch rows at 110 pounds per acre on November 6. This was four to six weeks later
than desirable. There was over 3000 pounds per acre of weeping lovegrass dry forage
present at the time. Starter fertilizer of 10-20-10 at 200 pounds per acre was banded with
the rye seed, and the rye was topdressed during February with ammonium nitrate at 200
to 300 pounds per acre. Total oven dry rye yields in plots ranged from 2100 pounds per
acre under no topdressing to 3700 pounds per acre with 67 pounds per acre actual nitrogen. First harvest weeping lovegrass oven dry yields were 2086 pounds per acre where
rye had not been grown, to 2304 pounds per acre where rye had been topdressed at 1000-0. The weeping lovegrass was topdressed during mid-March with 62-31-37 per acre,
regardless of rye topdressing. No adversities to weeping lovegrass have been noted other
than destroying a few clumps while drilling the small grain. The weeping lovegrass
roughage was grazed soon after the rye was planted. Grazing was then deferred until the
rye was grazed just before weeping lovegrass made early growth. Regrowth from the rye
was grazed when the weeping lovegrass was ready for early grazing. Even considering
the low level of management in this case, the system seems to have tremendous potential
in increasing the green season and productivity of weeping lovegrass pastures.
A John Deere LZ stubble mulch drill was used to plant the rye. Other pasture
drills could be used. Those with coulters in front of the shoe may not destroy as many
weeping lovegrass clumps. Drilling in weeping lovegrass, after much of the topgrowth
has been removed, would be better.
There are numerous ways the winter pasture and weeping lovegrass or other
perennials can be used, both overseeded and on clean seedbeds. Weeping lovegrass can
be grazed during fall and early winter with steers to be grazed later on small grains winter
pasture. Steers from small grain winter pasture have gained very well on early weeping
lovegrass. Refer to “How We Got 495 Pounds of Beef Per Acre” in this proceedings. A
system of grazing wheat, weeping lovegrass, and sudan has been reported (4). Other
programs involving small grains winter pasture for cows and calves have been published
(1, 2). Some of these involve using weeping lovegrass as a dry roughage and green small
grains as a protein supplement or creep feed.
Hay: A part of many intensive forage systems is harvesting excess forage as hay,
or maintaining a separate meadow. If the excess is not harvested, it is best winter grazed
or burned. Weeping lovegrass can make very good hay if it is properly harvested.
76
It is best to cut for hay four to seven weeks after a nitrogen topdressing, being
sure the quality has not receded greatly. It should be cut before excessive leaf tip browning or yellowing of foliage has begun. Cutting should be done at 30 percent or less seed
head emergence. Much weeping lovegrass is cut too late for better quality hay. When
cutting after grazing, the same basic guides to cutting should be used. However, it is
often necessary to cut later than would be recommended for hay meadows. Weeping
lovegrass may be cut for hay after seed harvest.
Quality can vary from low quality hay, testing only 4 to 5 percent protein, to high
quality leafy hay, testing 10 to 12 percent protein.
“Wild” bromegrass in perennial pastures: Various “wild” bromegrasses, including Japanese brome, downy brome, and rescuegrass, often infest bermuda grass and other
improved pastures. These grasses have largely been viewed as weedy species in the
pasture. However, with nitrogen fertilizer application and grazing management, the
grasses can be turned to an asset and can be used as valuable forage in many cases. They
are regularly occurring in many areas and have the potential to produce several thousand
pounds of grass before bermudagrass is growing. By topdressing with nitrogen early
(when the annual grass begins to grow during spring), these grasses can be produced to
an advantage. There are cases where over forty cow unit days per acre have been realized
before green bermudagrass is available. They have been produced and grazed to great
advantage in between graze-out of some winter small grains and summer grazing of
bermudagrass. The value in feed saved and additional gains can be great. Although the
quality may not be as good as some other chosen forages, it is quite acceptable. Forage
from these grasses has tested up to over 20 percent crude protein. If grown, they should
be relatively well utilized, as a heavy mulch buildup seems detrimental. In some pastures, these grasses may need to be controlled while others are to be grazed.
In some cases, these grasses can be available before weeping lovegrass. They can
be utilized first, weeping lovegrass second, with further grazing on the bromegrasses and
other summer forage as needed.
77
References
1. Dalrymple, R. L. Weeping lovegrass management. Noble Foundation, Ardmore,
2. Elder, W. C. 1967. Winter grazing small grains in Oklahoma. Okla. Agr. Exp. Sta.
Stillwater, Oklahoma. Bul. 654.
3. McIlvain, E. H. U.S. Southern Great Plains Field Station. Woodward, Oklahoma.
Personal communication.
4. McIlvain, E. H. and M. C. Shoop. Grazing weeping lovegrass. Okla. Agr. Exp. Sta.
Stillwater, Oklahoma. Fact Sheet 2558.
Q. How much weeping lovegrass was on the area at rye overseeding time?
A. Three thousand pounds per acre (oven dry).
Q. Wouldn’t it be better to graze it more to reduce the residue at drilling time?
A. You could graze it more than we did in this case. This was a first year stand, and this
year was dry, so we deferred all utilization until winter to allow the weeping
lovegrass to develop as much as possible. Under many circumstances, we could use
more fall utilization, but we would still want some growth left in the fall. We would
not want it slicked off. McIlvain and McMurphy spoke about detriments of short fall
mowing. Grazing is another form of mowing, and we would not want it short as this
could do some damage. It could be grazed shorter than this was.
78
Ermelo Lovegrass in the Renner Systems
Donald J. Dorsett, Agronomist
Texas Research Foundation
Renner, Texas
Ermelo lovegrass is a strain of common weeping lovegrass that was selected for
superior production capability in the Ermelo District of South Africa. It was put in the
Texas Research Foundation grass nursery in 1954. Grazing trials at the Foundation
indicated that Ermelo was one of the most productive grasses ever tested at Renner in
terms of pounds of beef per acre. Ermelo lovegrass was subsequently used with Coastal
bermudagrass, DeSoto grass, small grains, button clover, or fescue to form an integrated
year-round forage system known as the Renner Pasture System.
In the early 1960s, in an effort to furnish information concerning these grasses
and their management to livestock raisers, Texas Research Foundation entered into a
demonstration program. In this large-scale demonstration program, areas of 150 acres or
more were developed and managed by local farmers and ranchers for six years according
to Renner Pasture System guidelines. Texas Research Foundation personnel supervised
all phases of the development and management.
Since its inception, this program has grown to include twenty-six demonstration
sites involving more than 7,000 acres over a large portion of central and east Texas. The
area covered by this program is bounded on the southwest by Brown County, on the
northwest by Young County, on the northeast by Red River County, and on the southeast
by Nacogdoches County. Work with these demonstrations has given Texas Research
Foundation information and experience on a large variety of soil types and under varied
rainfall conditions.
Results obtained on these demonstrations have been very gratifying and indicate
their success. In most instances, overall carrying capacity has been doubled or even
tripled. Increased usage of fertilizer and better grazing management is evident in the
local areas. Ermelo lovegrass has been especially useful and productive. By using
Ermelo as a winter forage, demonstrators have been able to reduce the cost of wintering a
cow to one-half their normal cost. Little or no hay requirement has been helpful by
reducing the amount of labor needed for feeding. In the 40-inch rainfall area in
Henderson County, a demonstrator has obtained 131 days of winter and spring grazing
stocked at a high rate of 4.9 animal units per acre. In the 27-inch rainfall area of Young
County, established Ermelo lovegrass stands have furnished 120 days of continuous
winter forage stocked at one animal unit per acre with an additional seventy days of
spring grazing stocked at two animal units per acre.
An indication of the success of these demonstrations and their results can be seen
in the increased usage of Ermelo lovegrass in the demonstration areas. An estimated
8,000 to 12,000 acres of Ermelo was seeded in 1969 in the Houston-Anderson Soil and
79
Water Conservation District. The Trinity-Neches Soil and Water Conservation District is
including planting of Ermelo in each new conservation plan. In the Hood-Parker District,
an estimated 20,000 acres has been planted since the demonstration was established at the
Neeley Ranch.
The Renner Pasture System includes the use of three perennial warm-season
grasses—Ermelo lovegrass, Coastal Bermudagrass, and DeSoto grass—to provide a yearlong forage system. Small grains, clovers, fescue, and sudans can be used to supplement
the system if they are desired. All grasses are established in separate pastures for grazing
management purposes. All pastures receive fertilizer applications twice yearly to take
advantage of two peak growth periods of spring and fall.
Coastal bermudagrass is used as both a grazing and hay pasture. It provides high
quality grazing from May through July and from September into November. Coastal
bermuda produces good quality hay throughout the growing season. Its ability to produce
under high fertility rates makes Coastal an excellent improved pasture grass.
DeSoto grass—developed by Texas Research Foundation—is a variety of perennial
forage sorghum well adapted to supply succulent, green forage. It produces high quality
forage from mid-June through October, but its prime use in the Renner Pasture System is
during the hot, dry period of late July and August. DeSoto grass is drought tolerant and
furnishes a succulent, sweet forage at a time when most other grasses are restricted in
growth. DeSoto grass is also used as a “filler” grass in reseeding native rangeland in west
Texas. Because of its sweetness and palatability, cattle restrict their grazing primarily to
DeSoto and allow the native grasses to establish themselves and set a seed crop.
Ermelo lovegrass can be an excellent improved pasture under fertility and grazing
management. It has the advantage of greening up four to six weeks earlier in the spring
than other warm-season grasses. It produces high quality forage at a much needed time.
After a semidormant period during midsummer, Ermelo enters a second peak growth period
that can be grazed as green forage or conserved for a winter forage program. Because of its
fiber content, Ermelo cures well in the field and can be used as winter forage. The growth
characteristics of Ermelo have allowed it to be included in the Renner Pasture System under
two different management plans.
Winter and Spring Grazing: East of Fort Worth, in the higher rainfall belt,
Ermelo lovegrass has proven its value as a winter dry forage pasture and early spring
pasture. In the blacklands and sandy lands of east Texas, producers have been limited
largely to an annual small grain or clover pasture and a haying program. There has
always been the problem of dependability of these annual pastures, especially for the
December through February period. Ermelo lovegrass has proven useful in filling this
period as a dry forage pasture. Management for this type of use is keyed to two production periods of Ermelo. In late August, remove all standing forage to a 4- to 5-inch
stubble height, then fertilize with at least 50 pounds per acre of all needed major nutrients. All growth from that time until frost is left in the pasture to be used as field-cured
forage. After other grasses in the pasture system are grazed to the desired level, cattle are
80
put on Ermelo pasture with some form of protein supplement, salt, and minerals. Normal
grazing dates on the demonstrations of east Texas begin from November 15 through
December 15. Stocking rates during this period vary from two animal units per acre to a
high of 5.7 animals per acre. Recommended rates are two to three units per acre on a
mature stand. Grazing of dry forage generally lasts through February when the animals
are removed from the pasture. A spring fertilizer application of 50 to 70 pounds per acre
of nitrogen is then applied and two to three weeks allowed for regrowth. Spring grazing
starts on green forage around April 1 with stocking rates of two to five animal units per
acre. Green grazing extends into June and requires only salt and minerals as supplement.
Using this management system, the Thomas Walker demonstration in Henderson County
has reduced the cost of wintering his cow herd from 23.5 cents per head per day to 11.5
cents per head per day (including fertility costs). The following chart is the grazing
summary for Ermelo lovegrass on the Walker demonstration:
Year
Generally Nov.–May
1966-1967
1967-1968
1968-1969
Days
Utilization
117
110
131
Animal Units
per Acre
2.9
4.5
4.9
Animal Unit
Grazing Days/Acre
346
487
648
At the Neeley demonstration in Parker County, 121 Angus cows with 114 calves
were carried on 90 acres of Ermelo lovegrass from calving in November and December
until weaning in August except for two brief artificial insemination periods. The 90 acres
are divided into two 45-acre pastures for rotation purposes. Total fertility for the grazing
period was 150-50-0 with a 50-50-0 per acre fall application and a 100-0-0 per acre
spring application. The calves were weighed off the pastures on August 12 and averaged
436 pounds. This amounted to 552 pounds of calf per acre of Ermelo lovegrass. The
following chart is the grazing summary for Ermelo lovegrass on the Neeley demonstration:
Grazing Period
April 11–May 27
July 14–August 12
Animals
121 cows, 114 calves
121 cows, 114 calves
Daily Gain (Pounds)
Cows
Calves
2.07
1.98
1.01
2.50
Spring and Fall Grazing: West of Fort Worth, where rangelands are used in
conjunction with the Renner System, Ermelo lovegrass is well adapted for early spring
and late fall grazing. In these operations, improved pastures of Ermelo lovegrass, Coastal
bermudagrass, and DeSoto grass provide the bulk of the grazing during the frost-free
period with rangeland pastures used as winter pastures. This management is keyed to
improvement of the native grasslands through growing season deferment. In early
March, fertilize the Ermelo pasture with at least 50 pounds per acre of all needed major
81
nutrients. Grazing with two animal units per acre generally begins around April 1 and
lasts into June. The animals are then switched to other improved pastures. In early
September, at least 50 pounds per acre of nitrogen is applied, and grazing starts about
October 15. Stocking rates are one to two animal units per acre until most forage has
been removed. The animals will generally be shifted to rangeland in late December for
the winter period.
Summary
Ermelo lovegrass has proven its usefulness as an improved pasture grass in central
and east Texas. It can be used effectively with other improved pasture grasses to form a
year-round forage system. Ermelo lovegrass can be extremely useful in reducing the cost
of overwintering a cow herd, from both reduced labor requirements and reduced feed
costs. Ermelo also produces high quality grazing during the growing season and is
capable of producing over 500 pounds of beef per acre. However it is used, top production from Ermelo lovegrass requires a good fertility program and proper grazing management.
Q. Why do you plant weeping lovegrass in wide rows (36 inches)?
A. At first, this was because one of two planters we had would handle the seed. We
have gone more to broadcast planting. Our demonstrators who have both seem to
like the broadcast stand better than the wide row. Broadcast stands are rougher on
equipment, but furnish good, fine forage.
Q. On broadcast plantings, do you cover, and if so, how?
A. Covering takes a second trip over the field with a roller. The seed is broadcast on the
soil surface or drilled very shallow before rolling.
Q. Have you overseeded weeping lovegrass in native grasses?
A. We have accidentally at Brownwood, Texas. There was some weeping lovegrass in
the seeder, and it came up as a mixture. The next year, more was tried. It has
worked relatively well. Early spring grazing has resulted in taking the forage down,
so there has not been any old growth from year to year. When he rests the pasture
for a full growing season, and old growth is left tall, he will likely have trouble
managing the weeping lovegrass with the indiangrass and DeSoto grass in the
mixture.
Q. Does DeSoto grass have a toxicity problem after a freeze?
82
A. We have not lost cattle on it, but we do indicate that it has this type problem. We
would prefer giving it a two-week grazing-free period after frost.
Q. How much winter will DeSoto tolerate?
A. We have had no problem with it at all, but it must be managed as a tall grass. If it is
grazed very short in October, it will not stand much winter. We try to leave a 3- to 4foot stubble going into the winter. We may graze the leaves off in October, but leave
the stalk for protection. We have had no problem this way.
Q. Have you tried anhydrous ammonia in weeping lovegrass?
A. Only one time, in rows. It is easy to run the applicator shank between the rows
without damage to the plants. We hesitate to do this on broadcast plantings due to
expected plant loss.
Q. What is an electric cyclone seeder?
A. The seeder bin holds about 80 pounds of weeping lovegrass seed. There is a slit
door at the bottom to set, to meter out the seed. It has a fan blade under the opening.
A 13-volt electric motor, under the blade, turns the blade and broadcasts the seed in
about a 16-foot swath. It can be used as a three-point hookup on tractors, or it can be
pickup mounted.
Q. Do you have any DeSoto grass in the 25-inch belt around Vernon, Texas?
A. No, but we have some around Olney, Texas, and have had no survival problems.
Our cooperators have shipped seed to a man from the 9-inch rainfall belt of New
Mexico.
83
Grazing Studies on Weeping Lovegrass
in North Central Oklahoma
W. E. McMurphy
Agronomy Department, Oklahoma State University
Most of the grazing studies reported here were conducted when nitrogen cost 15¢
per pound and steers sold for 20¢ per pound. Therefore, only low levels of N fertilization
were used or no fertilizer was applied. These studies do serve a purpose in revealing
some of the palatability characteristics, the time of growth, and productivity at a low level
of management.
Red Plains Conservation Experiment Station, Guthrie: A six-year evaluation of a
weeping lovegrass–King Ranch bluestem mixture for pasture was conducted through the
drought years of 1950–1955 (Daniel et al., 1956). The pasture was on a formerly cultivated, badly eroded, Class VII site.
The pasture was fertilized with an average of 40 pounds N per acre each year,
stocked at a rate of 2 acres per 586-pound steer, and grazed for an average of 106 days.
Thus, grazing ceased in early August.
The steers gained 2.04 pounds per day and produced 102 pounds of beef per acre.
These results are encouraging when we consider that these were Class VII eroded soils, a
drought prevailed, and only 40 pounds of N was used.
The apparent compatibility of a mixture of weeping lovegrass and King Ranch
bluestem should not be overlooked.
Preferences of steers: The relative preference of steers for a number of species
was reported by Dwyer et al. (1964). In a three-day grazing period on May 22 and again
on August 7, weeping lovegrass was not grazed, but all the major native grass species, as
well as King Ranch and Caucasian bluestem, were grazed. These data verify rancher
observations on the necessity of having a fence to keep cattle on weeping lovegrass.
A very interesting aspect of that study is not in print. These weeping lovegrass
plants, which were not grazed during the growing season, have been eaten to the ground
each winter.
Steer grazing at Perkins, 1964: In the summer of 1964, ten 450-pound steers
grazed 10 acres of weeping lovegrass from April 20 to October 26 (Elder, 1965). Abundant rainfall in August and September produced a long growing season and excellent late
summer steer gains. Daily gain averaged 1.25 pounds for the entire season with 240
pounds beef produced per acre. These were the best results ever from this pasture, and
1965 results were not as good. Only 50 pounds of nitrogen per acre was applied.
84
Winter grazing at Perkins, 1964–65. If weeping lovegrass is grazed properly,
there should be a considerable amount of forage left by frost. This standing forage is
necessary to insure the health, vigor, and survival of the plants, but it must be removed
before spring growth commences. Winter grazing would be the ideal method.
Following the summer grazing by steers, the Perkins pasture was used to winter
cows with a stocking rate of 1.25 acres per cow. Protein supplement was provided by
grazing a rye-vetch pasture for one day out of six for November and December. During
January and February, the cows grazed the rye and vetch one day out of five. In March,
the cows grazed rye and vetch one day out of four until calving, at which time they were
turned into the rye-vetch pasture full time.
This combination of rye-vetch plus weeping lovegrass was apparently adequate
because there was no loss of weight (Table 1) up to calving, and total weight loss after
calving was only 5 percent.
Table 1. Wintering Cows on Weeping Lovegrass with Rye-Vetch Restricted Grazing1
Nov. 12, 1964
Feb. 15, 1965
Mar. 25, 1965
Avg. Wt. of Cows
1030
1035
975
1
Elder, 1965.
An examination of the ability of this system to meet the nutrient requirements of
dry cows is given in Table 2. Protein and energy will probably be the major limiting
factors in lovegrass. The crude protein content of rye (Fig. 1) through the entire season
was reported by Baker and Tucker (1967). Sullivan (1969) reported that digestible
protein was related to crude protein in that percent digestible protein = 0.88 (percent
crude protein) – 2.73. Using this same formula, the 3 percent crude protein in dried
lovegrass has no digestible protein value.
When examined on a weekly basis, one day a week on rye and six on lovegrass
would be below the minimum requirements in digestible protein and TDN (Table 2). If
rye is used for two days and lovegrass for five days, the ration is excellent for digestible
protein and just adequate for TDN.
The system tested started with one day on rye and five days on lovegrass. This
would be adequate for digestible protein, but slightly below the TDN requirements.
However, if the cow eats 20 to 25 pounds of rye instead of 18 pounds, then the ration is
adequate. In late pregnancy, a slightly higher digestible protein requirement is necessary
for the developing fetus, and the digestible protein of rye begins to drop in late March.
Thus, additional grazing of rye will be necessary. The rapid spring growth of rye makes
it an excellent pasture to provide protein in the winter and then full time quality forage
when the calf is born.
85
Table 2. Nutritional Requirements for Wintering a Dry 1100-Pound Cow and the Nutritional Content of Weeping Lovegrass and Rye
Daily requirement
Seven-day requirement (weekly)
Dry
Matter
18 lb.
126 lb.
Weeping lovegrass
Rye
Composition of winter forage
100%2
None3
2
100%
20%
Six-day lovegrass
One-day rye
Pasture systems
108 lb.
0
18 lb.
3.6 lb.
43.2 lb.
11.9 lb.
3.6 lb.
55.1 lb.
0
7.2 lb.
36.0 lb.
23.8 lb.
7.2 lb.
59.8 lb.
Inadequate weekly total
Five-day lovegrass
Two-days rye
90 lb.
36 lb.
Adequate weekly total
1
Taggert and Pope, 1968.
Based on oven dry weight.
3
Estimated after Sullivan, 1969.
4
Estimate based on dry native grass.
5
Morrison, 1951.
2
86
Dig.
Protein
0.6 lb.
4.2 lb.
TDN
8.5 lb.
59.5 lb.
40%4
66%5
30 –
%
20 –
10 –
Dec.
Jan.
Feb.
Mar.
Apr.
May
Figure 1. Crude protein of rye and estimated digestible protein (Sullivan, 1969) through
the winter
Weeping lovegrass and Old World bluestems: The Old World bluestems
(Bothriochloa spp.) have been in the breeding and testing program for several years, and
some releases of new varieties are expected in the near future. Testing the compatibility
of a pasture mixture of weeping lovegrass and Old World bluestem is beginning. If they
are not compatible as a mixture, then they should be considered for separate pastures side
by side.
The Old World bluestems start active growth in mid-May and do not make much
growth until June. Lovegrass would supply early grazing until the Old World bluestems
come into production. The Old World bluestems make excellent growth in August and
September if moisture and nitrogen are available. Furthermore, steer gains in these two
late summer months have been excellent (Table 3). Even the July gains have been better
than any from the bermudagrass studies.
87
Table 3. Average Daily Gain from Steers on Old World Bluestem Pasture at the Eastern
Oklahoma Pasture Station, Muskogee
Year
Month
April
May
June
July
August
September
1
2
1966
0.70
0.70
1.00
1.55
2.10
1967
1.60
1.60
0.60
1.50
1.50
1.00
None
None
19681
2.37
2.30
1.00
1.00
1.99
2.26
Fertilization
65-30-152
19691
3.47
1.97
1.75
0.94
1.64
1.53
65-30-152
Sod seeded to rye; thus the April-May grazing was on rye.
Rye received a 15-30-15 starter fertilizer and 50 N was topdressed in midsummer.
Therefore, the possibility of weeping lovegrass for early grazing and Old World
bluestems for late summer grazing appears to have excellent potential. Preliminary
information indicates that midsummer nitrogen application will be a must to insure
adequate forage quality in late summer.
Summary
The full potential of well fertilized and properly managed weeping lovegrass has
not yet been demonstrated in North Central Oklahoma, but enough information is available to excite the imagination. Winter grazing of weeping lovegrass is a recommended
method of removing the old forage, and rye can be used to supplement this winter forage
with protein and TDN. The compatibility of weeping lovegrass and Old World bluestem
looks promising in theory, and grazing tests are underway.
88
Literature Cited
Baker, J. M., and B. B. Tucker. 1967. Wheat fertilization research, progress report 1966.
Okla. Agr. Exp. Sta. Proc. Series 563. 38 p.
Daniel, H. A., H. M. Elwell, M. B. Cox, and B. B. Tucker. 1956. Field day guide and
summary of soil and water conservation and management research at the Red Plains
Conservation Experiment Station, Guthrie, Oklahoma. Mimeo. Report Okla. Agr.
Exp. Sta. 10 p.
Dwyer, D. D., P. L. Sims, and L. S. Pope. 1964. Preferences of steers for certain native
and introduced forage plants. J. Range Manage. 17:83-85.
Elder, W. C. 1965. Grazing studies on bermudagrass and lovegrass. Agron. Field Day,
Perkins Research Station, Aug. 27. Okla. Agr. Exp. Sta.
Morrison, F. B. 1951. Feeds and feeding. 21st Ed. The Morrison Publishing Company,
Ithaca. 1207 pp.
Sullivan, J. T. 1969. Chemical composition of forages with reference to the needs of the
grazing animal. USDA-ARS 34-107. 113 pp.
Taggert, W. F., and L. S. Pope. 1968. Winter feeding the beef cow. Okla. Agr. Ext. Serv.
Fact Sheet 3004.
89
Nutritive Value and Grazing Comparison of Weeping
Lovegrass and Other Summer Grasses
R. L. Duble
Texas A & M University Agricultural
Research and Extension Center
Overton, Texas
Summary
Forage produced from weeping lovegrass and other warm-season perennial
grasses can meet the requirements of beef cattle for normal growth if properly utilized.
Animal performance on warm-season grasses is a function of available forage and forage
digestibility. In trials conducted at Overton in northeast Texas, Coastal bermudagrass
produced more beef per acre and provided more grazing days per acre than weeping
lovegrass, bahiagrass, and common bermudagrass. The carrying capacity of weeping
lovegrass was close to that of Coastal bermudagrass, but poorer animal performance on
weeping lovegrass offset its high carrying capacity. Forage digestibility, forage intake,
and animal performance were highest on Coastal bermudagrass and poorest on weeping
lovegrass pastures. All perennial summer forages were characterized by a high fiber
content and a low digestibility during midsummer. The energy, protein, and mineral
intake from these forages was sufficient to meet the requirements for growing animals
most of the summer. To attain maximum pasture productivity, summer forages must be
intensively managed. Liveweight gains per acre were highest on all grasses when utilized
at high stocking rates during months of maximum forage production. Adjusting stocking
rates to maintain available forage near 800 pounds per animal and harvesting excess
forage maximized pasture productivity on weeping lovegrass and other summer grasses.
Introduction
Permanent summer pastures provide the foundation for most beef cattle operations. Forage production from permanent pastures is seasonal by nature, with production
peaks in the spring and late summer. Weeping lovegrass (Eragrostis curvula),
bermudagrass (Cynodon dactylon), bahiagrass (Paspalum notatum), and other warmseason grasses have similar characteristics. Forage growth patterns from these grasses
are overlapping and are not complementary to one another. However, with proper management, forage can be conserved to complement growth patterns. Animal performance
on conserved forage is generally poor, whether harvested or left standing. Efficient
utilization of these grasses requires intensive management of available forage. To
achieve maximum pasture productivity, forage must be utilized before its nutritive value
deteriorates. The decline in nutritive value and animal performance with forage maturity
has been noted in most forage species. It is the purpose of this paper to present information relating species and stocking rates to liveweight gain per acre, forage utilization, and
the nutritive value of forage consumed.
90
Experimental Procedure
Grazing trials were conducted at Overton in 1969 to compare production potentials
of several warm-season perennial grasses and to relate characteristics of forage quality to
animal performance. Established stands of common weeping lovegrass, common and
Coastal bermudagrass, and Pensacola bahiagrass were utilized for grazing trials. Plantings
of Coastcross-1 bermudagrass and kleingrass-75 were evaluated by in vitro techniques. All
pastures were established on upland, sandy loam soils with a pH range from 5.7 to 6.4. The
grasses were in pure stands by the spring of 1969 with the exception of the bahiagrass
pasture, which contained some common bermudagrass. Each grass used in grazing trials
was established in two 5-acre pastures and was grazed continuously at two stocking rates
ranging from 0.8 animal per acre on bahiagrass to 2.0 animals per acre on Coastal
bermudagrass and weeping lovegrass (Table 1). Yearling, F-1 Brahman-Hereford heifers,
wintered to gain 0.8 pounds per day, were used to estimate animal performance (Figure 1).
The average weight of the heifers was 585 pounds when they were put on pastures. Animal
performance was estimated from weights taken at twenty-eight-day intervals.
Figure 1. Yearling, F-1 Brahman-Hereford heifers on Coastal bermudagrass (foreground)
and weeping lovegrass (background), 1969, Overton, Texas
Fertilizer was applied to all pastures on four dates at six-week intervals for a total of
200-100-100 pounds per acre of N-P2O5-K2O. Excess forage was harvested from Coastal
bermudagrass and weeping lovegrass pastures on June 9. Pastures were dragged with a
chain harrow at six-week intervals to scatter manure piles. To control broadleaved weeds,
two applications of 2,4-D + Banvel D were made to all pastures except bahiagrass.
Forage samples were taken from each pasture the day animals were put on pastures
and at two-week intervals thereafter. Each sample represented available forage at the time
it was taken. Samples were immediately frozen and subsequently freeze-dried. Dry
samples were ground to pass a 1-mm sieve and stored in tightly sealed amber bottles.
91
Forage samples were analyzed for protein, fiber constituents (hemicellulose, cellulose,
and lignin), in vitro dry matter digestibility (IVDMD), and minerals (P and Ca).
Nitrogen was determined by the micro-kjeldahl procedure and crude protein
calculated as Nx 6.25 (1). Fiber constituents were determined by Van Soest’s detergent
procedures (6). The Tilly-Terry two-stage fermentation procedure was used to estimate
dry matter digestibility (4). Phosphorus was determined colorimetrically with ammonium molybdate, and calcium was determined with a Perkin-Elmer atomic absorption
spectrophotometer. Digestible energy was calculated from Van Soest’s detergent fiber
analyses (5).
Estimates of available forage and forage intake were taken at monthly intervals
using the “cage difference” technique described by Robinson et al. (3).
The summer of 1969 was extremely dry in east Texas, and forage production was
below average on all pastures. Consequently, grazing pressure was heavy on highly
stocked pastures, and available forage became limiting on all pastures during July and
August. Nevertheless, cattle remained on pastures stocked at 1.2 animals per acre or less
without supplemental feeding until November 3. Coastal bermudagrass stocked at 2.0
animals per acre produced the greatest liveweight gain per acre of all pastures (Table 1).
Weeping lovegrass stocked at 2.0 animals per acre produced approximately the same
liveweight gain per acre as common bermudagrass and bahiagrass pastures stocked at 1.5
animals per acre. Although weeping lovegrass had a considerably higher carrying capacity than common bermudagrass and bahiagrass, liveweight gain per acre was offset by
poorer animal performance. Liveweight gain per acre increased with stocking rate on all
grasses up to the stocking rate where available forage became limiting.
92
Table 1. The Effects of Species and Stocking Rates of Warm-Season Grasses on
Liveweight Gain, Carrying Capacity, and Animal Performance, 1969, Overton, Texas
Pasture
Coastal
Bermudagrass
Weeping
Lovegrass
Common
Bermudagrass
Pensacola
Bahiagrass
Stocking Rate
Animal/Rate
2.5*
2.0
1.2
2.3*
2.0
1.2
1.6
1.0
1.4
0.8
Liveweight Gain
per Acre
670
550
401
490
356
303
361
272
330
240
Animal Days
per Acre
430
322
235
370
252
252
224
196
204
156
*Estimated liveweight gain per acre, assuming 1 ton of hay harvested is equivalent to 120
pounds liveweight gain and 108 grazing days per acre.
Coastal bermudagrass and weeping lovegrass were understocked at 2.0 animals
per acre during the first two months of the grazing trial. Consequently, excess forage
from these pastures was not utilized. If stocking rates had been adjusted to utilize the
excess forage, liveweight gains per acre would approach 670 and 490 pounds for Coastal
bermudagrass and weeping lovegrass, respectively (Table 1). Animals utilized essentially
all of the forage produced on common bermudagrass and bahiagrass pastures, and
liveweight gains per acre produced on these pastures, stocked at 1.5 animals per acre,
represent maximum pasture utilization. Since conditions vary from month to month, it is
impractical to use a fixed stocking rate. Thus, a basis is needed by which stocking rates
can be adjusted to obtain maximum forage utilization. Available forage and growth rate
provide the criteria by which stocking rates can be adjusted. Since growth rate can only
be predicted for a short period, stocking rates must be adjusted on the basis of available
forage. The relationship between average daily gain (ADG) and available forage for
several permanent summer pastures is shown in Figure 2. Maximum animal performance
occurred when available forage was near 1000 pounds of dry forage per animal. If gain
per animal is more important than gain per acre, then available forage should be maintained near this level. However, Riewe (2) has shown that maximum liveweight gain per
acre occurs when gain per animal is less than maximum. Thus, to achieve efficient
forage utilization, available forage should be maintained near 800 pounds per animal.
The irregular growth patterns of summer grasses makes “put and take” stocking or mechanical harvesting essential to maintain this level of available forage.
When available forage was not limiting, animal performance was significantly
greater on bermudagrasses and bahiagrass than on weeping lovegrass. Also, weeping
93
lovegrass and Coastal bermudagrass showed a decrease in ADG when available forage
was greater than 2000 pounds per animal. These differences in ADG can be explained by
the quality of available forage.
Figure 2. The relationship between available forage and animal performance on summer
pastures, –bermudagrass, –weeping lovegrass, 1969, Overton, Texas
Forage quality, expressed in several terms, influenced animal performance
through limiting intake and digestibility. Characteristics measured to describe forage
quality included protein, total digestible nutrients (TDN), and in vitro dry matter digestibility (IVDMD). All of these variables were positively correlated with intake and animal
performance. The digestibility of available forage from weeping lovegrass was approximately 12 percent lower than from Coastal bermudagrass at every two-week sampling
period (Fig. 3). The digestibility of common bermudagrass and bahiagrass was similar to
Coastal bermudagrass. Estimated intake by grazing animals was also less on weeping
lovegrass than on other grasses. The combination of lower digestibility and intake levels
accounted for poorer animal performance on weeping lovegrass than on the other grasses.
The quality of Coastcross-1 bermudagrass and kleingrass-75 expressed in terms of digestibility was superior to Coastal bermudagrass and weeping lovegrass throughout the
summer. Thus, we could expect better animal performance on these improved varieties
of bermudagrass and kleingrass. However, the range of adaptation and carrying capacity
of these new varieties has not been definitely established.
94
Figure 3. The digestibility of four summer grasses throughout their growing season,
1969, Overton, Texas
Digestibility alone did not fully describe forage quality. The ruminant has specific requirements for protein, carbohydrates, minerals, and vitamins. Protein provides a
source of ammonia, and carbohydrates provide a source of energy. Since protein is an
inefficient source of energy and carbohydrates do not furnish ammonia, these requirements must be considered individually. Therefore, the intake of each of these nutrients
was estimated from the chemical composition of the forages and their estimated intake by
grazing animals (Fig. 4–7). The National Research Council’s (NRC) estimated nutrient
requirements for normal growth of heifers and steers are also shown for each nutrient.
The intakes shown are estimated from pastures stocked with 1.2 heifers per acre. Dry
matter intake for Coastcross-1 bermudagrass was assumed to be the same as for Coastal
bermudagrass. Since available forage was limited on these pastures during July and
August, nutrient intake was limited by available forage as well as by forage quality.
However, estimated forage intake suggested that intake was primarily limited by the high
fiber content of available forage (Table 2). Weeping lovegrass and Coastal bermudagrass
were characterized by an extremely high fiber content during July and August, which
significantly limited the intake of digestible energy. Coastcross-1 bermudagrass was the
only forage studied which met the digestible energy requirements for normal growth of
heifers throughout the summer (Figure 4). Digestible protein intake exceeded the
animal’s requirement for protein throughout the summer on Coastal and Coastcross-1
bermudagrass (Fig. 5). Only during July and August was digestible protein intake deficient on weeping lovegrass pastures. Phosphorus and calcium intakes may be deficient
on all summer pastures after July 1, because the availability of these minerals was not
considered in the calculated values (Figs. 6 and 7).
95
Table 2. The Relationship between Estimated Forage Intake by Grazing Animals and the
Cell-Wall Content of Available Forage, 1969, Overton, Texas
Cell-Wall Content
of Available Forage
(Percent)
55
60
65
70
75
80
Forage Intake*
(Pounds DM/Day)
26.0
22.5
20.0
17.0
12.0
9.5
*Intake was influenced by other variables such as protein content and temperatures;
however, the cell-wall content of available forage explained 78 percent of the variability
in forage intake.
Figure 4. Digestible energy intake by cattle grazing three species of summer pastures
without supplemental feed, 1969, Overton, Texas
96
Figure 5. Digestible protein intake by cattle grazing three species of summer pastures
without supplemental feed, 1969, Overton, Texas
Figure 6. Phosphorus intake by cattle grazing three species of summer pastures without
supplemental feed, 1969, Overton, Texas
97
Figure 7. Calcium intake by cattle grazing three species of summer pastures without
supplemental feed, 1969, Overton, Texas
98
References
1. Association of Official Agricultural Chemists. 1965. Official methods of analysis.
10th Ed. Washington, D. C. 20036.
2. Riewe, Marvin E. 1961. Use of the relationship of stocking rate to gain of cattle in
an experimental design for grazing trials. Agronomy Journal. 53:309-313.
3. Robinson, R. R., W. H. Pierre, and R. A. Ackerman. 1937. A comparison of
grazing and clipping for determining the response of permanent pasture to
fertilization. J. Amer. Soc. Agron. 29:349-359.
4. Tilley, J. M. A. and R. A. Terry. 1963. A two-stage technique for the in vitro
digestion of forage crops. J. Brit. Grassland Soc. 18:104.
5. Van Soest, P. J. and L. A. Moore. 1965. Proceedings: 9th International Grassland
Congress. Sao Paulo. 783-789.
6. Van Soest, P. J. and R. H. Wine. 1967. Use of detergents in the analysis of fibrous
feeds. IV. Determination of plant cell-wall constituents. J. Assoc. Off. Anal.
Chem. 50:50-55.
99
Q.
Did you say that animals did not lose weight on weeping lovegrass and did on
Coastal bermuda?
A.
Yes, but the weeping lovegrass was stocked at one animal per acre and the Coastal
at two animals per acre. On Coastal stocked at one animal per acre, we never did
go below 1 pound per day on animal gains.
Q.
What is the rainfall belt?
A.
About 50 inches annually, but the distribution is poor—it all comes at once.
Q.
Why did you use continuous rather than rotation grazing?
A.
We have 10 to 12 acres of each species. These are split into two pastures and
stocked continuously at two different stocking rates. The idea was to develop a
relationship between stocking rate and gain per acre, which we have been able to
do. Other than that, I don’t have an answer. The size of the pastures is about 5
acres, and if we split them again, there would be a watering and labor problem.
We haven’t gotten a lot of difference on permanent grasses grazed continuously or
rotationally.
Q.
What did the samples represent in terms of available forage?
A.
The samples were taken from the pastures every two weeks and did represent
available forage at that time under grazing.
100
What We Did to Get 495 Pounds of Beef
per Acre from Weeping Lovegrass
The high potential forage productivity and early season production of weeping
lovegrass has been variously demonstrated for years. Turning this forage into beef
production is basically the summary of this report.
The Noble Foundation’s Sturm Farm has been used for years as a pasture demonstration unit. Ermelo and other weeping lovegrass varieties, King Ranch bluestem,
Midland and Coastal bermudagrass, and native ranch are represented in the pastures.
Some of the improved grasses and the native range have been used to evaluate heifer or
steer performance and forage characteristics and potential. Various data has been collected from the farm since 1964, but of primary interest here is the heifer and steer pasture data of 1968 and 1969.
Pasture Management: The weeping lovegrass and bermudagrass pastures were
established during 1964–65. The King Ranch bluestem pasture is much older with no
known establishment date. The bermudagrass and King Ranch bluestem pastures are in
good stands with the exception of insignificant small areas. The weeping lovegrass
pasture is good except in about 30 percent of the area where it is only about 50 percent of
a full stand.
Soils of the area are typically complex, but basically represent extremely shallow
to moderately deep sandy loam and sandy clay loam soils of southern Oklahoma. The
weeping lovegrass is on the poorest area, with considerable gravelly, droughty soils
represented. The King Ranch bluestem is on the best, least eroded soil, leaving Midland
bermudagrass on the medium desirable soil in this case.
Each pasture was managed as intensively as thought practical with residue burning (weeping lovegrass only), fertilization, and two-pasture rotation. Weeping lovegrass
residue was burned during moist surface soil conditions on March 4, 1968, and February
26, 1969. This was just as major spring growth began. Advantageous response to burning was extremely good. The greater the residue, the greater the need to burn, and the
greater the response from it. More information on burning is given in associated plot data
later in this report (Tables 8 to 12).
Fertilization schedules are presented in Table 1. All nitrogen was from ammonium nitrate (33.5-0-0). The last topdressing in all cases was ineffective for summer
grass production due to dry weather. Fertilization and grazing data from 1968 on weeping lovegrass, bermudagrass, and King Ranch bluestem has been previously published
101
(2). During 1968, the weeping lovegrass received a total of 284-40-40; nitrogen was
applied four times. This amount of total nitrogen may seem too high, but in order to
maintain high quality and production, it is needed if moisture is adequate. Scheduled
applications are vitally important. One should remember that if a nitrogen deficiency is
visible, it is already past time for another application if quality and production are to be
maintained at a high level. It is also important to note that the second topdressing on
weeping lovegrass comes when bermudagrass and King Ranch bluestem are ready for the
first topdressing. This is when all species are being individually managed, as
topdressings are applied at the beginning of their respective growing seasons.
Table 1. 1969 Pasture Fertilization Schedule
Weeping Lovegrass
Vetch–
Midland Bermudagrass
Vetch–
King Ranch Bluestem
Feb. 26
0-40-40
With vetch
0-35-35
With vetch
0-35-35
Mar. 20
61-0-0
Apr. 30
67-0-0
Apr. 30
67-0-0
Apr. 30
67-0-0
Jun. 18
67-0-0
Jun. 23
74-0-0
Jun. 9
71-0-0
Totals
134-35-35
141-35-35
199-40-40
A “hand grab” forage sample was taken periodically from each pasture. High and
low analyses from each species are presented in Table 2. All forages tested high in
chemical components early in their season and tapered to a low near the termination of
the steer grazing season. Had precipitation allowed for better regrowth, more fluctuation
would have been likely.
Table 2. 1969 Pasture Chemical Composition
% Prot.
% Phos.
1
2
Plant
H
L
H
L
Native grass
8.8
3.3
.17
.05
Weeping lovegrass
19.8
7.2
.27
.08
Bermudagrass
17.6
5.7
.28
.10
King Ranch bluestem
15.2
8.8
.22
.12
Hairy vetch
29.3
19.3
.49
.32
% Pot.
H
L
.81
.37
.82
.42
1.00
.57
.93
.69
2.40 1.10
% Dry Mat.
H
L
66.0 29.9
62.5 22.0
63.6 38.9
64.9 22.7
21.3 15.7
H1 = High.
L2 = Low.
Rotational grazing was on two pastures within each improved pasture. The steers
were generally rotated when a given pasture was grazed to a 3- to 6-inch height and as
the associated paddock contained more and presumably better forage. The two-pasture
102
rotation system was better than experienced with one pasture and worked well the first
six weeks to two months. After this period, pastures were either ahead or behind the
rotation. Native range was not rotationally grazed.
As the weeping lovegrass produced seed heads, they were shredded to clean up
the pastures and attempt to get better regrowth. This was relatively ineffective. One
should be careful not to mow a heavy buildup of residue and leave it on the pasture; a
heavy full cover of mowed residue will smother weeping lovegrass plants. Under a good
rotation system, cattle will preferably graze weeping lovegrass heads during the boot to
full seed head stage. The heads are much higher in chemical analysis components than
the rest of the plant, and this is probably instrumental in the grazing preference (Table 3).
Table 3. Chemical Composition of Weeping Lovegrass Seed Heads1
Plant Part
Seed head
Rest of plant
Seed head
Leaf
Stem
%
Dry Mat.
13.0
26.2
68.0
50.0
41.0
%
Prot.
13.6
10.8
13.1
8.4
6.4
%
Phos.
.28
.13
.29
.11
.14
%
Pot.
1.14
.74
.55
.41
.70
1
Composite of several years and several pastures.
Soil moisture was excellent until late June. From June 14 to July 29, a total of
0.56 inch of rain fell in four showers. There were twenty-one days of 100o F or higher
temperatures during this period. The first general rain after June fell during mid-October.
These facts must be considered in evaluating pasture condition and animal performance.
The pastures regrew slightly or none during this period. Some drought kill was noted in
King Ranch bluestem and weeping lovegrass pastures. Weeping lovegrass wilted first,
but remained predominantly green throughout the season. King Ranch bluestem showed
drought stress next, and soon dried up completely; however, its protein content remained
good. Good steer gains during this period are attributed to this. Midland bermudagrass
and native grass dried up soon after King Ranch bluestem, but remained very slightly
green to the end of July.
Stocking was begun the first week in April on early weeping lovegrass growth
and overseeded vetch in bermudagrass and King Ranch bluestem. Steer groups averaged
about 450 pounds. In general, the weeping lovegrass was stocked at one steer per acre to
mid-April, then the stocking rate was built up to four steers per acre on April 22. This
rate was reduced to 2.6 steers per acre on June 3 when one group was sold. This rate was
maintained until all steers were removed on July 29 to be sold. The vetch-bermudagrass
and vetch–King Ranch bluestem pastures were stocked much lighter. The weeping
lovegrass was capable of carrying two to three times the stocking rate of the excellent
hairy vetch, and steer gains were much better. After vetch graze-out, the bermudagrass
103
was stocked at about one steer per acre, and King Ranch bluestem at about one-half steer
per acre. The native range was lightly stocked, but for purposes of calculation, a rate of 3
acres per steer was assumed.
Two groups of steers were used. One group was newly purchased commercial
steers of #1 Okie type, and the second was a similar type that had been pastured on
various small grain winter pasture programs for sixty-three days prior to their grazing.
This is an example of how two different programs can be blended together. That is,
steers from intensive winter pasture may be carried over during spring and early summer
on high quality spring and summer forage. This can allow a high early stocking rate of
pastures such as weeping lovegrass. Thus, one can realize more from these pastures at
their peak period.
Livestock Management: Most newly purchased steers were lotted, worked, and
placed on pasture within one day of purchase. A few steers were bought during February
and were fed a maintenance ration of hay plus protein supplement. All new steers were
vaccinated for blackleg and malignant edema, treated with Ruelene for grubs, wormed
with Thibenzole, and implanted with 12 mg Stilbestrol before pasturing. Flies were
controlled with Marlate dust.
Due to extremely dry forage, the steers were fed 5 pounds of 17 percent protein
range cubes per day (five days per week) during the last two weeks. This was done to
preserve gains for contract delivery of August 1.
Results
It is impractical to report all data collected from the pastures in this report. However, the more important data is presented. Three years of grazing and beef production
from Ermelo weeping lovegrass is presented in Table 4. During 1967, heifers gained 1.81
pounds per day on weeping lovegrass from early June to early August after grazing early
bermudagrass growth. Soil moisture was excellent. During 1968, early season gains were
2.00 to 3.17 pounds per day, but dropped to losses of 0.42 pound per day during late June
due to maturing forage. Gains picked up to 1.96 pounds per day during July on regrowth
after alternately haying the pastures. Table 5 gives more detailed data for 1969 on weeping
lovegrass and other pastures. Animal gain data is presented in Tables 6 and 7.
Table 4. Grazing Days and Beef Production per Acre from Ermelo Weeping Lovegrass—
Ardmore, Oklahoma
Grazing Days/Acre
Pounds
Total
Beef/Acre2
Year
Summer
Winter1
1967
171 (heifers)
266
437
309
1968
273 (heifers)
138
411
251
1969
315 (steers)
50
365
495
Average
252
151
403
352
1
Used for maintenance of cows, bulls, and heifers. Some hay feed days in the total for
1968.
2
Based on summer grazing only.
104
Table 5. Pasture Production/Acre from All Steers—1969
Total
Steer
Pounds
Grazing
Forage
Beef/Acre
Days/Acre1
Native Range
59
31
Weeping Lovegrass
495
315
Vetch–Midland Bermudagrass
241
151
Vetch–King Ranch Bluestem
171
122
Residual
Grazing
Days/Acre2
Total
Grazing
Days/Acre
50
33
14
365
184
136
1
Summer only.
Grazing days per acre from fall and winter roughage as grazed by cows, bulls, and
springer heifers.
2
Table 6 gives the seasonal gains of steers previously grazed on good small grain
winter pasture. The steers grazed winter pasture in various limited and continuous
grazing programs. However, the trends in average daily gains were basically the same as
for the continuous grazing group, so they are all grouped as one in this case. Gains on the
vetch-bermudagrass pasture were not as good as vetch–King Ranch bluestem. Early
gains on weeping lovegrass (May 7) were comparable to early gains on King Ranch
bluestem (June 3). Vetch constituted little of the forage after mid-May. More discussion
on vetch and weeping lovegrass is presented in these proceedings under “Weeping
Lovegrass in Integrated Forage Systems.”
Table 6. 1969 Average Daily Gain of Winter Pasture Steers1
Forage
Weeping lovegrass
Vetch–King Ranch bluestem
May 7
2.29
1.00
June 3
1.48
2.26
Overall
ADG
1.94
1.55
1
Previously grazed winter pasture sixty-three days. Began grazing these pastures April
22. The overall gain on winter pasture was 2.16 pounds per day.
Seasonal gains of newly purchased steers are presented in Table 7. The weeping
lovegrass steers did well until mid-June. From a gain potential standpoint in this case,
they would surely have done better on the other grasses after June 18. This is illustrated
by a group not shown in the table. Five low-gaining steers were moved from weeping
lovegrass to bermudagrass on June 18. These steers gained 0.85 pound per day to July
29. This was still low, but was much greater than that of the steers left on weeping
lovegrass for the same period. Under limited rotational facilities that result in maturing
forage and when other midsummer forage is higher quality, it would be wise to rotate to
better pastures. The only weight losses were from steers on bermudagrass during the last
period. On July 29, weeping lovegrass had higher protein levels, less dry matter, and
much more green forage than bermudagrass. This likely is the reason better gains were
received on weeping lovegrass than bermudagrass.
105
Table 7. Pounds Average Daily Gain from New Steers—1969
Forage
Native range
Weeping lovegrass
Vetch–Midland bermudagrass
Vetch–King Ranch bluestem
May 16
2.50
2.29
1.46
1.32
June 18
2.24
1.77
2.86
1.84
July 15
—0.07
1.78
2.15
July 29
1.27
0.40
-0.13
0.46
Overall
ADG
1.88
1.13
1.25
1.34
The weeping lovegrass pasture was the most profitable under this system. During
1968 and 1969, over 90 percent of the beef produced per acre was realized by mid-June
on weeping lovegrass, and the pounds of beef per pound of nitrogen was 1.18 and 2.49
respectively. Bermudagrass and King Ranch bluestem pounds of beef per pound of
nitrogen was much less.
Urine spots normally show up as darker green and more productive areas, but
urine dead spots as large as three feet in diameter were noted in the weeping lovegrass
pasture. The steers grazed, and thus urinated, in this pasture just as drought started. With
the progressive drying, the grass completely died in the spots. This was on an extremely
droughty soil site. It was not noted in any other pastures.
Plot Studies: Burning and fertilizer plots were observed in conjunction with
weeping lovegrass pastures. Residue burning was done as new growth started in the
spring, four to six weeks before grazing began. This was late February to early March.
The first nitrogen topdressing was during mid-March with successive topdressings after
each hay cutting. Ammonium nitrate (33.5-0-0) at 200 pounds per acre was used each
time. A total of four topdressings to equal 268 pounds of actual nitrogen per acre was
applied in 1968, and three topdressings to equal 201 pounds of actual nitrogen was
applied in 1969. All plots received 0-40-40 per acre annually. Average total production
is given in Table 8. Early season fluctuation in production and chemical composition was
noted between burned and unburned areas, but this leveled off during midsummer.
Burned areas regrew faster and made more early production. When the burning time is
right, green grass available for proper grazing can be advanced up to seven to ten days.
This can be very important if feeding is being done or earlier grazing is needed. At no
time, during ten years of spring controlled burning observations in various pastures, has
an adverse effect on forage production or quality been noted. Initial growth after burning
is often very chlorotic or white, but turns very dark green in a few days. Clumps regrow
sooner and more rapidly on the southern exposure side. This growth is often 2 to 6
inches tall before the north side regrows. Proper burning controls many annual weedy
plants in weeping lovegrass pastures. When deciding whether to burn or mow old residue, one should consider the quality, availability, and production advantages of burning.
Comparatively, shredding does little good and can do much damage. From a forage
standpoint alone, shredding offers no advantages over proper burning.
106
Table 8. Weeping Lovegrass Yields from Control Burned and Nitrogen Topdressed Areas
(Pounds per Acre Oven-Dry)
1
Treatment
Control
Burned only
Fertilized only
Burned and fertilized
1968
5,439
6,556
10,431
10,186
1969
6,811
7,142
9,651
9,713
2 year
Average
6,125
6,849
10,041
9,950
1
All received 0-40-40 each year.
Tables 9 and 10 represent early season forage chemical data. After the first hay
cutting during May, major differences were from nitrogen fertilization. Although we
have not checked animal gains on burned versus unburned areas, it is highly probable that
they are better on burned areas. This would especially be likely as more old residue was
accumulated in unburned pastures. Kansas research has shown animal gains to be significantly better on spring control-burned native range ten out of fourteen years (1). Weeping lovegrass responds to proper residue burning as well as, or better than, native range.
It would be very surprising if better gains were not received, especially during the first
six weeks to two months of grazing.
Table 9. Influence of Burning and Nitrogen Topdressing on Chemical Composition of
Early Weeping Lovegrass Forage—1968
% Prot.
Treatment
4-3
4-24
Control
—
11.2
Burned only
—
12.6
Fertilized only
11.8
13.0
Burned and fertilized 19.7
13.8
% Phos.
4-3
4-24
—
.16
—
.18
.17
.20
.24
.18
% Pot.
4-3
—
—
.69
.87
4-24
.88
.97
1.10
1.30
Table 10. Weeping Lovegrass Chemical Composition from Burned and Nitrogen
Topdressed Areas (First Harvest—Two Year Average1)
%
%
%
%
Treatment
Prot.
Phos.
Pot.
Cal.
Control
7.5
.17
.48
.10
Burned only
8.3
.15
.58
.09
Fertilized only
8.6
.15
.61
.09
Burned and fertilized 9.8
.16
.65
.09
1
May 23, 1968, and May 5, 1969.
Extraction of nutrients from the soil is important. Tables 11 and 12 reveal the
removal per ton of forage and per acre for this two-year period. Based on the removal,
107
the phosphorus rate of 40 pounds per acre annually has probably been sufficient, but 40
pounds of potassium has been insufficient. The actual sufficiency depends on the nutrient
uptake efficiency.
Table 11. Pounds of Nitrogen, Phosphorus, and Potassium Removed/Ton1
Actual
Treatment
Nitrogen
P2O5
K2O
Control
21
5.2
7.8
Burned only
23
5.3
9.1
Fertilized only
25
5.6
11.2
27
5.6
11.4
1
Based on all harvests (1968 and 1969).
Table 12. Pounds of Nitrogen, Phosphorus, and Potassium Removed/Acre1
Actual
K2O
Treatment
Nitrogen
P2O5
Control
63
16
24
Burned only
80
18
31
Fertilized only
125
28
56
132
28
57
1
Based on all harvesting (1968-1969).
Tables 13 and 14 give other data on nitrogen topdressed and nontopdressed areas.
The average responses help portray characteristics of nitrogen.
Table 13. Topdressing Influences on Weeping Lovegrass Pastures (from Two Years of
Data)
Item
Pounds protein/acre
% Protein–all sample average
% Protein–mid winter
% Green–lowest winter sample (field weight)
% Green–at Christmas (field weight)
108
Nontopdressed
421.0
8.5
4.9
1.4
38.0
Topdressed
803.0
10.5
6.0
4.7
54.0
Table 14. Protein Percentage of Green and Dry Portions of Standing Weeping Lovegrass
Treatment
Nontopdressed
Topdressed
2-18-69
Dry
Green
4.3
5.6
5.3
6.0
2-17-70
Dry
Green
3.4
7.5
4.4
8.1
Average
Dry
Green
3.8
6.6
4.9
7.1
References
1. Anderson, K. L., E. F. Smith, and C. E. Owensby. 1970. Burning bluestem range. J.
Range Manage. 23:81-92.
2. Dalrymple, R. L. Weeping lovegrass management. Noble Foundation. Ardmore,
Q.
Have you used any liquid nitrogen for topdressings?
A.
Not on weeping lovegrass. We have had plots in bermuda, and the response was
much less. During 1967, the overall average of liquid nitrogen (28 percent) was
about 50 percent as good as ammonium nitrate (33.5-0-0). This difference is
probably a little more severe than the normal. During 1968, on a better grass area,
liquid nitrogen was 60 to 92 percent as good as 33.5-0-0 depending upon comparative treatments. Overall, liquid nitrogen averaged 74 percent of 33.5-0-0.
This was from the first cutting—no further cuts were made.
Q.
Was the potassium fertilization level low on this pasture?
A.
Based upon the plant analyses from harvested forage, we are definitely removing
more than we are adding. We plan to alter our applications to apply more than we
extract from the soil. I imagine we will start applying about 60 pounds per acre of
potash per year. We do not like a deficiency to show in yields or looks, and this is
the reason we apply nitrogen at more or less monthly intervals. We would not
need to do this with potassium. If a nitrogen deficiency begins showing, nitrogen
application is already late. Our phosphate levels are probably about right.
Q.
Do we need to apply lime on a strongly acid soil?
A.
Specifically, I don’t know. I haven’t seen any weeping lovegrass liming information from this country. Weeping lovegrass is one of our most acid-tolerant
grasses. However, acid alone is not all that is involved. Nutrient availability, as
influenced by soil pH, is important. Liming would also depend on fertilization
109
levels used. Fertilization will increase the acidity of the soil. As a critical point is
reached, liming would likely be needed. Need for liming shows up more quickly
under high production levels. A bermuda study in Georgia showed that, at lower
levels of nitrogen, liming response was low. At high nitrogen levels, liming was
more responsive.
King Ranch bluestem fertilization plots on the Noble Foundation’s Sturm farm
can give an idea of pH changes. Under moderate to high fertilization for King
Ranch bluestem, the pH went from about 6.8 initially to as low as 5.4 in three
years. This was with 100 pounds per acre actual nitrogen with and without
phosphorus and potassium. Fertilization of weeping lovegrass can be much higher
than this, so it is difficult to say how low the pH may go.
Q.
Were the yields of weeping lovegrass under no burning and fertilization significantly different from burning and fertilization?
A.
There was a very small difference in total yields, but this was only about 100
pounds per acre when the total yield was about 10,000 pounds. This wasn’t
attributed to treatment significant differences. There were differences early in the
growing season in favor of burning.
Q.
Can we reseed open or thin areas in a pasture to make the stand uniform?
A.
I have tried this a number of times, but it seems to end with the spot again. There
are often soil reasons for the spot grazing to appear. There may be better soil
moisture, soil fertility, an extremely poor soil, etc., at the spot, causing severe
grazing and die out. If these characteristics are not altered, the problem can
reappear. A rotation to allow regrowth on the spot can help.
Q.
Is there a sulfur response on weeping lovegrass in east Texas?
A.
A gentleman in the audience said he saw several references in literature that
reported no sulfur response on bermuda in east Texas. This might be applicable to
weeping lovegrass.
110
Grazing Weeping Lovegrass for Profit—8 Keys1
Woodward, Oklahoma
Summary
Our research shows that eight keys to the grazing use of weeping lovegrass are
essential for high profits. The keys should be used in about this sequence, starting in
March each year:
1. remove old growth;
2. fertilize;
3. let spring growth get 6 inches tall (rest during April);
4. use at forty-day intervals (graze for one week, rest for five weeks);
5. cut or graze to a 4-inch stubble;
6. control spot grazing;
7. rest during Sept., Oct., and Nov. and then winter graze;
8. use in combination with other forages—each in its season.
Why Manage Lovegrass?
Weeping lovegrass produces immense forage yields, which can be highly profitable only if the grass is managed properly.
Weeping lovegrass (hereafter called lovegrass) has the potential to yield 300–500
pounds of beef and 5,000 to 8,000 pounds of hay per acre on upland soils in Oklahoma
and throughout the Southern Plains—without irrigation. To produce these high forage
and beef yields, lovegrass must be managed as tame pasture—it cannot be used the way
we customarily use native range.
Lovegrass is being widely planted in Oklahoma. Over 150,000 acres are now
well established in the state, and another 150,000 acres are growing in Texas.2 Only a
1. A progress report based on cooperative studies conducted by the Crops Research Division, Agricultural
Research Service, U.S. Department of Agriculture, and the Oklahoma Agricultural Experiment Station,
Stillwater, Oklahoma.
111
few of these acres are being properly managed for high yields and profits. Many acres
are being mismanaged and are producing low yields, low cattle gains, low profits, and are
being killed out by spot grazing, fall grazing, lack of or too much fertilizer, and other
causes.
The purpose of this progress report is to emphasize to lovegrass growers what our
research has constantly emphasized to us—the need for high-level grazing management.
Our studies are still in progress. Some management keys may be revised later, and others
may be added.
Different management may be needed in the drier and colder areas of Oklahoma
than in the warmer and wetter areas. Some management practices discussed by
Dalrymple2 for south central Oklahoma do not apply in northwestern Oklahoma. For
instance, fall grazing is suggested for the south central area, but this practice kills or
injures our lovegrass and also has caused it to winterkill at Fairview and Hennessey.
Similarly, the high rate of nitrogen (50 to 100 pounds actual nitrogen per acre per
application) suggested for use in south central Oklahoma causes summer die-out in
northwestern Oklahoma during severe dry spells. Each grower—particularly those
midway between Ardmore and Woodward—must manage his lovegrass with care until
we have more research and grower experience.
Grazing Research in Northwestern Oklahoma
Our lovegrass research has been conducted for more than thirty years, and we
now have grazing experiments in progress on forty pastures of lovegrass. This grass has
been used on ranches in northwestern Oklahoma for twenty-five years, but mostly as
“range” and not as “pasture.” Although the grass is not new, the grazing practices required for high profits are quite new to those of us who have grazed and managed only
native range.
Lovegrass in western Oklahoma seems best adapted to sandy soils such as the
Pratt series, but careful observations of lovegrass growth and use have been and are being
made on other soils including Woodward, Quinlan, Vernon, Miles, Brownsfield, Nobscot,
and Tivoli. Our observations indicate that similar grazing practices are required by
lovegrass on a wide variety of soils.
Key 1—Remove Old Growth
Old growth comes in two ages (last year’s and this year’s), and both must be
removed if lovegrass is to be profitable! Of course, the best solution to the old-growth
problem is to prevent it, and this can be done by following the other seven keys.
2. Dalrymple, R. L. 1969. Weeping lovegrass management. The Noble Foundation. Ardmore, Oklahoma.
112
Previous year’s old growth: If by March 1 the old growth is rank and unusable,
the most practical solution is to burn it. If the old growth is rather spotty and thin on the
ground and obviously will not smother new grass, it can be (1) burned, (2) mowed and
left on ground, or (3) grazed off with a high concentration of stocker cattle. Steers used
to “mow” the old growth must be fed a daily ration of 2 or 3 pounds of a high protein
supplement.
Current year’s old growth: If forty-day-old growing forage cannot be uniformly
and completely grazed off within about one week’s time, it should be mowed at once
either for hay or for litter.
Burning lovegrass: Old accumulations of lovegrass growth have been burned at
Woodward for the past fifteen years—without injury to the plants. Grass should be
burned from February 15 to April 15 just as it starts spring growth. Proper burning
conditions include (1) adequate fire guards, (2) adequate fire fighters, (3) at least 2 feet of
subsoil moisture to assure start of spring growth, (4) a moderate wind, and (5) a little
moisture, at or near the soil surface, to dampen the underside of the litter and the base of
the living plants.
When lovegrass is burned under these prescribed conditions, it starts spring
growth much earlier and is much darker green in color. The forage is much more palatable and nutritious; the plants produce more seed heads and vegetative tillers (shoots); the
old dead tillers, which take up space within the grass clump, are removed; and much of
the litter is left on the soil.
Key 2—Fertilize
Nitrogen fertilizer is a must if lovegrass pasture is to be profitable. Nitrogen is
usually the only fertilizer needed to produce high yields in western Oklahoma. At least
when a pasture is young, concern should be primarily with nitrogen. Of course, in areas
of known phosphorus or other mineral deficiency, the shortage must be corrected.
Use ammonium nitrate: In research at Woodward, ammonium nitrate produced 24
percent more lovegrass forage than did urea. Other workers found that urea topdressed
on pastures can be as efficient as ammonium nitrate if applied immediately after a burn.
We have had no experience with nitrogen as a liquid or as a gas.
Use 30 pounds of nitrogen per acre each application: Our research shows that the
safest and most economical rate of nitrogen is about 30 pounds (actual) per acre for each
application. In northwestern Oklahoma, apply nitrogen about April 1, again on June 1,
and again on August 1 if the subsoil has at least 1 to 2 feet of moisture at about those
dates. This means that in a dry year, you might apply only 30 pounds of nitrogen. In
other years, you would apply either 60 or 90 pounds. Rates higher than these will cause
die-out during severe dry spells.
113
In the 30- to 50-inch rainfall areas of Oklahoma, rates of 150–200 pounds of
actual nitrogen per acre (in split applications) have been suggested.2
Die-out: Lovegrass on loam, silt, and clay soils in northwestern Oklahoma rather
consistently dies out during severe dry spells when fertilized with 60 pounds of actual
nitrogen per acre at one time, even if cut at forty-day intervals. This rate is not recommended.
Summer die-out on these soils can also occur from applications of 30 pounds of
nitrogen per acre if the grass is not cut at about forty-day intervals. The uncut plants
become tall and rank, use huge quantities of water, exhaust the subsoil moisture, and
either die or are injured. In brief, don’t overfertilize—use frequent, 30-pound applications.
Use whirlwind spreaders: The whirlwind fertilizer spreaders, available through
many fertilizer dealers, are efficient. We get the most uniform application (and the least
spot grazing) when we use a 30-foot swath even if the spreader is rated at a 35- or 40foot swath. Some large spreaders are rated at a 60- to 70-foot swath.
Use spreader trails: If flags or other travel guides are not used, fertilizer applications will be streaked, and this will cause spot grazing. A new technique is to make
spreader trails. Flag the pasture at 30-foot intervals (or wider), and use a single 12-inch
sweep on a three-point hook-up. Sweep about 2 inches deep to kill the grass for about 10
feet, then lift out for 10 feet. On steep slopes, make shorter killed strips. These skipstrips will be visible for several years, and they do not reduce forage production.
Key 3—Let Spring Growth Get 6 Inches Tall (Rest during April)
Grazing the early spring leaves of lovegrass reduces forage production for the
entire year. Depending upon temperature and soil moisture, lovegrass starts growth in
March or April, but usually only a few leaves per plant become “bite size” at any one
time. Several acres of the sparse growth must be allowed for each steer in order to
provide enough forage for high gain. The damage to the plants offsets the gain advantage to the few steers that can be grazed.
Lovegrass roots grow rapidly in April and May. The plant needs to manufacture
food to grow roots and forage at the same time. If the early spring growth is grazed off
two or three times, the plant cannot get its “food factory” into operation for high production.
114
Key 4—Use at Forty-Day Intervals
The key is to grow a crop of forage, and then harvest it while it is nutritious.
Lovegrass and alfalfa are alike in that they produce a crop that must be harvested on time
or wasted. Our cutting-date and stage-of-growth studies indicate harvests should be
made about forty days apart—either by a quick graze or by mowing.
Harvests made more often than every forty days prevent lovegrass from replacing
food reserves in its roots and from growing large crops of forage. On the other hand,
when lovegrass leaves get past forty days of age, they rapidly lose palatability and nutritive value. Digestibility also declines rapidly.
The suggested grazing schedule is to graze for one week and rest for five. Each
pasture will be grazed about three times during the period May 1 to September 1. The
aftermath growth produced in the fall can be grazed in midwinter.
Key 5—Cut or Graze to a 4-Inch Stubble
Four good reasons for cutting or grazing lovegrass to leave a 4-inch stubble are
to (1) grow more forage, (2) prevent die-out, (3) make a stubble barrier, and (4) produce
more profit!
When lovegrass is harvested to leave 4 inches of stubble, the base of many green
leaves continues to manufacture food for new rapid growth. The small tillers that help
grow the next crop are not cut off. Also, a high stubble reduces and, in many instances,
prevents winter injury.
Stubble barrier: Mowing lovegrass to leave 4 inches of stubble creates a
“pincushion” to keep cattle from repeatedly grazing the plants to ground level.
Understanding the way lovegrass grows helps to understand the principles of
using it. Each new tiller grows from the woody stem base near ground level. The tiller
produces about seven to nine leaves, and then a seed stalk may or may not emerge. After
the tiller matures, it becomes semidormant or dormant, and it eventually dies even if
moisture and fertility are adequate. During this period, it produces little or no green
forage. Further plant growth must come from a new tiller—similar to alfalfa.
As dead tillers become numerous, each new tiller must find room to grow. The
most room is usually around the outside of the plant, and the plant centers soon support
few live tillers. Burning seems to be the best way to get rid of old tillers, and it needs to
be done for this purpose only on an as-needed basis—probably once each three to seven
years.
115
Key 6—Control Spot Grazing
Steers on spot-grazed pastures have gained 50 to 80 pounds per head less during
summer than similar cattle on uniformly grazed pastures—even though grass on the spotgrazed pastures was plentiful! In addition, grass on a spot-grazed pasture is hurt by both
overgrazing (die-out in the spots) and undergrazing (smothered by old growth).
Cause: Lovegrass grows 1 to 2 inches per day when moisture and fertility are
adequate. A plant grazed off on one day will have bite-size growth on it two or three days
later, and this growth is the youngest and most delicious in the pasture. Cattle seek the
tender, high-moisture regrowth avidly, and they will not eat the coarser (older) growth.
Therefore, their daily forage intake falls below nutritional requirements for rapid gain.
Prevention and control: There are five practical ways to prevent and control
destructive spot grazing. It will usually be profitable to use all five methods on every
lovegrass pasture.
Stubble barrier: Create a 4-inch-high stubble barrier with a mower or a
swather.
Flash graze and rotate: Stock each pasture division with enough cattle to
graze all useable forage within one week. This usually means putting ten to
fifteen steers on 1 acre. Obviously, a rotation plan must be used if the grass is to
be rested between harvests. A minimum of six pasture divisions must be used so
that the grass can be grazed for one week and rested for five.
Spot mow: After a pasture division is grazed for about one week and the
cattle are moved to the next division, the unused plants should be mowed at a 4inch stubble height. If the mowing is delayed for three or four days, the regrowth
on the mowed spots will be three or four days younger than the other growth on
the pasture—and the mowed spots will be grazed first when this pasture division
is again grazed.
Spot fertilize: When the area left ungrazed is fairly large, about 30 pounds
of nitrogen can be applied prior to mowing or swathing the unused growth. This
additional nitrogen increases palatability and will help control spot grazing for
several years.
Use all other tools: Other tools which can and should be used to distribute
cattle grazing pressure include wise location of (1) water, (2) salt, (3) supplemental feeding, (4) shade, (5) rubbing posts for insect control, and (6) fences to create
pastures with uniform soil and topography.
116
Key 7—Rest during Sept., Oct. and Nov.
In northwestern Oklahoma, vigorous, productive stands of lovegrass can be
winterkilled by close use in September, October, or November.
Effects of fall use: Grazing or mowing lovegrass to a 2-inch stubble height in
September, October, or November has killed 30 to 70 percent of the plants and weakened
the remainder. Studies conducted since 1962 show that the injury and die-out occurs
every year. However, the die-out may be highest in September in one year and in either
October or November the next year.
Cause of kill: We do not know what causes lovegrass to die when it is closely
used in the fall. We speculate that the plant is injured or killed because it does not usually
go fully dormant until December. Root reserves (carbohydrates) are depleted as the plant
struggles to make fall leaf growth. Also, rapid root growth occurs during September,
October, and November, and the plant may be weakened by the combined effects of
producing both root and shoot growth. Research is still in progress.
Key 8—Use in Combination with Other Forages
At Woodward, well-managed lovegrass usually produces enough forage on about
three-fourths of an acre to maintain a steer for eight months. Obviously, during a severe
drought, forage production will not be adequate. Unless large quantities of hay or grain
are fed during a drought, lovegrass must be used in combination with other forages.
Native range: An exciting relationship exists between the use of lovegrass pasture
and native range. When an area equivalent to 15 percent (15 acres out of 100) of a
pasture is seeded to lovegrass, cattle numbers can be doubled. For instance, in northwestern Oklahoma, a weaner steer can be carried yearlong on about 8 acres of native range.
Thus, a 320-acre pasture would carry forty steers. If 15 percent, or 48 acres, were planted
to lovegrass and managed properly, the 320 acres would carry eighty steers yearlong.
The 48 acres should be divided into six 8-acre pasture divisions. Starting when
the grass is 6 inches tall, about May 1–10, all eighty steers can be placed on one pasture
division. This gives a stocking density of ten steers per acre. If moisture and fertility
remain adequate, the eighty steers can be rotated to successive divisions and carried full
time on lovegrass until September 1. If drought occurs, and also after September 1, the
steers can be grazed as needed on the native range. A new crop of steers can then winter
graze the native range and the lovegrass after December 1. Severe prolonged drought
would naturally require reduction of cattle numbers.
Graze-out wheat and hybrid sudan: In our studies, 1 acre of well-managed
lovegrass pasture plus 1 acre of fertilized farmland was cropped to graze-out wheat and
then to graze-out sudan. This combination provided enough high-quality forage to carry
a steer for a year. The average grazing results for the past three years were as follows:
117
Program
Pounds of Gain per Steer
Wheat
Lovegrass
Sudan
to
to
to
May 1
Aug. 1
Oct. 1
Lovegrass
to
Mar. 11
Yearlong
Graze-out and
lovegrass (2 acres)
30
155
100
110
385
Native range
(8 acres)
—
—
—
—
380
1
Includes lovegrass hay in November.
Other tame pasture: Although we have not studied other tame pastures in combination with lovegrass, it is highly probable that 1 acre of well-managed bermudagrass
could easily replace the 3.4 acres of grass in the native range forage system outlined
above. If rainfall and fertility were adequate summer-long, hay would have to be made
on the bermuda or on both grasses to keep the forage young and nutritious for fall and
winter use.
It is also easy to foresee a profitable combination of lovegrass and Caucasian
bluestem or other Old World bluestems. Similarly, a pasture combination of lovegrass
and cool-season grasses, such as brome and fescue, could be put together for a high-profit
potential.
Plan for drought: Seldom do we have a year in the Southern Plains without one or
more periods of intense drought of 30 to 60 days’ duration. The pasture combinations
outlined above will normally provide the required flexibility. However, there will be dry
spells when supplements such as grain, hay, or silage must be fed. Cattle can be kept
gaining at 1.0 to 1.5 pounds per day during these dry periods by feeding a mixture of hay
or silage with a protein supplement and coarse-cracked sorghum grain. A fifty-fifty
mixture of hay and grain gives good gains and will help hold the cattle operation together
until it rains, and forage is again adequate.
In Conclusion
Don’t overplant lovegrass—it must be managed properly to be profitable, and
large acreages require much capital and labor.
118
Q.
Is there any difference on best clipping height on a large robust weeping lovegrass
plant and one that is typically smaller in stature?
A.
I may not know the answer, but it seems that a single lovegrass tiller, coming from
the crown of a plant, is an individual. A plant is a group of tillers. Each must be
managed healthily. There is a little cross-translocation from one tiller root system
to another, and this may aid one tiller to live on the roots of another tiller for a
while.
Q.
What is your thinking on more rapid rotation than every forty days—at least
during certain seasons?
A.
I think if you graze to a 4-inch stubble and allow regrowth two to four weeks,
then regraze, it won’t hurt if done occasionally. This is particularly after good
precipitation and with good fertility. This would allow for some good grazing and
profitable pasture. When the season gets tough, and you are trying for high
production, longer deferment periods are in order.
119
Over 200 Cow Units
on
480 Acres of Weeping Lovegrass
Frank Tidwell, Agricultural Representative
Security State Bank, Cheyenne, Oklahoma 73628
History bears out the fact that when you have no grass, you will be unable to
produce beef. We had this situation on a considerable amount of sandy land area in
Roger Mills County when the subject of our story, Mr. B. E. Clift of Reydon, Oklahoma,
started his grassland improvement program.
In order for you to fully comprehend the significance of what he has accomplished, we need to give you some historical background.
On November 27, 1868, the Cheyenne Indians under Chief Blackkettle engaged
George Armstrong Custer in one of Oklahoma’s most important Indian battles near the
present site of Cheyenne, Oklahoma. This battle is now known as the Battle of the
Washita. Mr. Clift believed that an area worth fighting for was worth developing.
As a result of overstocking and lack of moisture, much of our land originally in
bluestem mixture was invaded by shinnery oak as the predominant species. A lot of land
was plowed up to grow crops in the years prior to soil conserving practices. This resulted
in a great deal of wind and water erosion. Mr. Clift was faced with these two problems:
1. Shinnery oak infestation on undisturbed grazing land
2. Eroded farm land
Mr. Clift realized that a single individual wouldn’t be able to correct erosion
problems unless water runoff from his and adjoining land could be controlled. As luck
would have it, the Upper Washita Soil and Water Conservation District and the Soil
Conservation Service came into being just prior to this time. This Soil Conservation
District had the first fully completed Upstream Flood Prevention Project in the entire
world. Mr. Clift was one of the first cooperators of this district.
As one of the pioneers in soil conservation, Mr. Clift rapidly got his soil erosion
program completed. This left him with his shinnery brush problem. The following is the
story telling how Mr. Clift overcame these initial problems and developed land capable of
providing forage for 200 cows on 480 acres of land.
Four hundred eighty acres of lovegrass provides forage for 200 cows year-round
for B. E. Clift of Reydon, Oklahoma. His sandy land farm is located in extreme western
Roger Mills County, Oklahoma. This county has an annual rainfall of approximately 24
inches. This success didn’t just happen; it took lots of luck, work, expense, and planning
to realize success.
120
His story began in 1946 when he purchased a section of land consisting of
Nobscot-Brownfield soils covered with shinnery brush. He was faced with the problem
of making a living and paying for the land with income from twenty cows. This was the
maximum carrying capacity of that section.
A small acreage of the section was in cultivation. In attempting to farm this land
in row crops, Mr. Clift found that a small area was too much of a blow hazard to attempt
to farm. In searching for a solution to this problem, he purchased from his Soil Conservation District some weeping lovegrass seed, which he planted in 40-inch rows. The seed
cost was $4.00 per pound, and he seeded it at the rate of 1 pound per acre. This all
occurred in 1947, and by 1949, as a result of high seed yield, the area was solid set to
lovegrass.
At this point, Mr. Clift felt he had a plant suited only for control of wind erosion.
Cattle did not molest this grass when they came in contact with it. A couple of years
later, a neighbor accidentally burned the lovegrass off. The following spring, while his
cattle were grazing his cropland area, he noticed they were spending an awful lot of time
on the lovegrass. This convinced Mr. Clift that it was at least as good as his native grass
when it was burned off. After two years of burning as the only management practice, he
saw great potential for the lovegrass as a forage for beef production.
Since the brush pastures were only producing a small return on his investment, he
was determined to eradicate the brush and establish lovegrass. At this time, a limited
amount of similar soils in the area had been deep plowed. The result of this plowing 24
inches to 36 inches was a soil surface high in clay content, which was easier to manage
from the standpoint of wind erosion.
With the success of deep plowing of sandy soils on cultivated land in the county,
Mr. Clift reasoned that if he could turn the brush under and the clay soils up, he would
have a perfect situation for weeping lovegrass production. The high percentage of clay in
soil surface would reduce wind erosion hazards for a few years while he raised cotton,
broomcorn, and silage to defray the cost of the plowing operation.
With the large acreage that he had to plow, also thinking that his neighbors would
hire him to plow some similar fields, he felt that he might just as well own a crawler
tractor and a heavy disc plow. The day that the equipment arrived, he started the plow
into operation. He started plowing around the entire section. After farming this land for
three years, he was sure that the brush was eradicated to the point that it would not return.
He made sure that enough sorghum cover was left on the 480 acres that were to be seeded
to weeping lovegrass to protect it from wind erosion until the lovegrass was established.
He felt that 160 acres of the best soils should be left to provide a source of supplemental feed and cash crops to round out his program.
Mr. Clift was one of the pioneers in the use of fertilizer in Roger Mills County.
One spring, while applying anhydrous ammonia to his cotton ground, he acted on im-
121
pulse and made a complete round on his lovegrass. On this strip of fertilized grass, the
cattle observed the response before he did. Before the summer was over, Mr. Clift was
determined that he had rather spend money for fertilizing lovegrass than row crops and
commented that he was not about to stop fertilizing row crops. The next spring found
him following up with his burning and fertilizing program.
After deferring the first year, Mr. Clift generally burns the top grass residue. Fire
guards are a must. Neighbors don’t want their native pastures destroyed. The optimum
condition for burning was found to be moist soil condition, dry grass, and a brisk wind.
Burning is generally accomplished in mid-March. This allows maximum early growth
the first of April.
After burning, fertilizing with anhydrous ammonia is practiced. At least 100
pounds of nitrogen is used. Phosphate level is low on Nobscot-Brownfield soil. Experience has taught Mr. Clift that phosphate application will pay big dividends on these soils.
As a result, he is one of the first to take advantage of the soil testing program offered by
the Security State Bank of Cheyenne, Oklahoma. Mr. Clift is high in his praise of the
bank president, Mr. L. L. “Red” Males, for making this service available to the county.
Mr. Clift now had two management practices—fire and fertilizer. By using these
practices, he discovered that he had created another problem. He simply didn’t have
enough cattle. Through the years, he had increased his cow herd to fifty animal units. He
found that this herd could not utilize even 100 acres of his grass without cutting the field
into four equal size pastures to concentrate on smaller areas at one time. He now has
three management practices—fire, fertilizer, and cross fencing.
The other 380 acres were not a total loss. Mr. Clift harvested 100 pounds of seed
per acre from 30 acres, which he sold to his neighbors for $1.00 per pound. Acting on
impulse again, he decided to harvest the stubble for hay. He only harvested 40 acres,
which made 60 tons. This was an extremely dry year, and a local dairyman purchased
this hay for $18.00 per ton. His per-acre income that year from his ungrazed grass
amounted to $127.00 per acre. Total production costs, including harvesting, were $20.00
an acre, leaving him $107.00 profit. As a point of interest, his cotton crop that year
netted him $31.00 an acre.
Even though the net profit was attractive to Mr. Clift, he decided that he should
cash in on beef cattle. His reasoning was, even though he didn’t care to expose his age,
that after a fellow is sixty-five years old that he doesn’t have to buy a fishing license, and
he hasn’t needed to purchase one for several years.
He had a need to increase his cow herd to utilize the entire 480 acres. It was apparent that he needed a 200-cow herd. Mr. Clift reasoned that he needed a unique cow to take
advantage of the potential of the lovegrass. He decided to combine the milk producing
ability of the Holstein with the rapid growth characteristic of the Charolais. He imported
some high quality Holstein heifers from Wisconsin to start his program. He continued to
use Charolais bulls until he had all of the dairy appearance removed from the herd.
122
By 1969, he had developed a 200-cow herd. While developing his herd, he had
also developed a plan of action. He decided to use the four pasture, three herd, rotation
deferred grazing system. He now has four management practices—fire, fertilizer, fencing, and rotation deferment.
This is Mr. Clift’s success story, and it is working for him in western Roger Mills
County. Perhaps each area of the state has problems that are prevalent to that area. We
experienced an armyworm infestation in the summer of 1969. It is apparent that they
relish well-managed lovegrass. Mr. Clift says that this has been the only insect problem
in lovegrass production. He said that, with the exception of a small amount of emergency
hay, all lovegrass should be harvested by the cow. Take quantity, and add quality, and
you are in business. This applies to producing hamburger or lovegrass, says Mr. Clift.
Q.
What was the pasture rotation program?
A.
In the spring, after I fertilize, these subdivided pastures are grazed. It is not
uncommon to have 200 cows on 30 acres. They are there one to two weeks, or as
long as it takes to graze the pasture. Then we move them to another pasture. The
cows’ behavior will tell us when they need to be moved.
123
Winter Grazing of Weeping Lovegrass in Northwestern Oklahoma1
M. C. Shoop and E. H. McIlvain
Range Scientist and Agronomist
Woodward, Oklahoma
Summary
Well-managed weeping lovegrass (Eragrostis curvula [Schrad.] Nees) is highly
palatable to cattle during winter and produces excellent gains per head. During winter,
the dormant aftermath of weeping lovegrass (hereafter called lovegrass) is as palatable as
the dormant forage of blue grama (Bouteloua gracilis); and the dormant, overmature
forage of summer-rested lovegrass is more palatable than switchgrass (Panicum
virgatum) or little bluestem (Andropogon scoparius).
Lovegrass aftermath grown on fertilized pastures during September, October, and
November produced as much gain per steer during winter as high-quality native range—
about 1/2 pound per head per day. About 1 acre of aftermath was adequate to carry a steer
from December through March.
Steers wintered on summer-rested lovegrass (overmature) gained only slightly
less than steers on native range, and only about 1/2 acre was required to carry a steer from
December through March. We do not recommend this program, but it is one method of
using mismanaged, dormant lovegrass.
Winter grazing from December through March was not harmful to lovegrass.
However, grazing in September, October, or November caused winterkill. Also, grazing
short, young, new growth in April reduced summer-long production of forage.
Hay cut when lovegrass is about forty days old is high in quality and is eagerly
eaten by cattle. Steers fed high-quality lovegrass hay gain about 1 pound per head per
day when supplemented with a daily ration of 11/2 pounds of 41 percent protein (cake).
Also hay from older or coarser lovegrass, which is sometimes cut from pastures on an
opportunity basis, produced acceptable winter steer gains.
One and one-half pounds of 41 percent cake is an optimum daily feeding rate for
most yearlong grazing programs on lovegrass aftermath. Higher rates of protein and the
feeding of grain as a supplement are usually unprofitable. On summer-rested,
overmature lovegrass grazed from December through March, each additional pound of
cake above 11/2 pounds per steer per day increased gain 25 to 30 pounds per steer; thus,
daily caking rates of 21/2 to 31/2 pounds would be profitable if steers were sold at the end
of winter.
Oklahoma.
124
Introduction
Weeping lovegrass (Eragrostis curvula [Schrad.] Nees) should not be grazed in
September, October, or November. However, it should be grazed in midwinter to utilize
the forage economically. Weeping lovegrass (hereafter called lovegrass) that is not
winter grazed will have to be burned or mowed in the spring to keep old growth from
reducing cattle gains the next summer.
There are two basic kinds of lovegrass for winter grazing: (1) high-quality aftermath and (2) mismanaged, overmature grass. We recommend only the first kind, aftermath, for winter grazing. However, we recognize that a cattleman occasionally will have
and want to use overmature lovegrass. For example, he could acquire overmature
lovegrass on newly obtained land or on released “soil bank” land.
The purpose of this paper is to make available the results of several studies related
to winter grazing.
Area and Cattle
Grazing studies with lovegrass have been conducted since 1946 on the Southern
Plains Experimental Range in northwestern Oklahoma near Woodward. The eighty-fiveyear precipitation is 23 inches annually, of which 16 inches fall in summer. Average
snowfall is 15 inches. Drought periods occur frequently during the growing season.
Temperatures in January usually range from 20o F to 45o F, and in July from 70o F to 95o
F. Extremes are from –27o F to 113o F.
The predominant soil type on the rolling, stabilized, sand dunes is Pratt loamy
fine sand. All the soils have a single-grain structure that makes them highly susceptible
to erosion.
Our grazing trials were conducted on lovegrass and on native range pastures. The
results from native range serve as a basis of comparison for the results obtained during
the same period with lovegrass.
We used weaner steers as our experimental cattle. The steers were high-quality
Herefords obtained each year from the same ranch. They were received in October as
calves directly off the cows, were number branded, and were weaned and handled in a
single herd until they regained their weaning weight and were allotted. Allotment of
steers was at random within weight classes. Average beginning weight of the steers was
about 475 pounds.
No additional roughages were fed during these grazing trials. In all trials, the
steers were fed 41 percent protein cottonseed pellets (cake).
125
Experiments
Effects of Winter Grazing on Lovegrass
Procedure. Two replicated studies were conducted to determine the effect of
removing lovegrass during winter. In a four-year study, we mowed the previous
summer’s growth from plots on September 15, October 15, November 15, March 22,
April 5, and April 22.
In another study, we mowed lovegrass to a 4-inch stubble in late January. Adjacent areas were left all winter with all of their late-summer accumulation of growth and
were then mowed in late March. The areas were harvested the next summer to determine
the effect of winter removal of forage.
Results. Mowing in the fall caused 20 to 60 percent winterkill of lovegrass on all
dates. However, the date of mowing which caused greatest winterkill varied from year to
year. Mowing in September caused the most severe winterkill in two of the years. Mowing in October caused the most winterkill one year, and mowing in November caused the
most winterkill another year.
Lovegrass plots mowed April 22 had lower vigor and produced about 15 percent
less forage during summer than those mowed March 22. Plots mowed April 5 produced
about 5 percent less than those mowed March 22.
Mowing in January had no effect on forage production the next summer, as
compared with leaving the forage on until late March.
Discussion: Winter grazing should not start before a heavy freeze turns lovegrass
straw-colored—usually about December 1 at Woodward. In addition, grazing should stop
when lovegrass starts active growth in the spring—usually about April 1 at Woodward.
Related studies show that winter grazing should stop when lovegrass is grazed to
a 4- or 5-inch stubble height. The stubble forms a “pincushion” or “stubble barrier” that
keeps cattle from grazing lovegrass too closely.
Winter Grazing of Lovegrass Aftermath
Procedure: Grazing of lovegrass aftermath on common and ‘Morpa’ lovegrass
pastures was studied for three winters with two eight-head lots of weaner steers on each
variety. The pastures had been fertilized with nitrogen and grazed on a rotation basis
during summer. The steers were on pasture from about December 2 through March.
Results. The pastures grew about 1,200 pounds of grass per acre while being
rested from September through November. One acre of aftermath carried a 475-pound
weaner steer from December through March.
126
Steers on aftermath during winter gained the same as steers on native range
during the same period. The steers on Common lovegrass gained 54 pounds per head,
and those on Morpa lovegrass gained 65 pounds per head. In comparison, steers on
native range gained 55 pounds per head (Table 1).
The weaner steers ate the lovegrass aftermath readily. In fact, the aftermath was
as palatable and nutritious as was blue grama (Bouteloua grazilis) to steers in adjacent
pastures.
Morpa, a more palatable lovegrass, increased winter gain per steer 20 percent as
compared with common lovegrass. The higher winter gains, plus the subsequent higher
summer gains, made by steers on Morpa increased yearlong profits $12 per acre above
common.
Table 1. Winter Gain of Weaner Hereford Steers Grazed on (1) Weeping Lovegrass
Aftermath and (2) Native Range Grazed Yearlong1
Winter
1966-67
1967-68
1968-69
Average
Daily gain
Morpa
Lovegrass
64
75
56
Gain per Steer (Pounds)
Common
Lovegrass
58
54
50
65
54
.54
Native
Range
59
46
59
55
.45
.46
1
Lovegrass pastures were fertilized in April or May each year.
Discussion: A 475-pound weaner steer on lovegrass during winter eats about 10
pounds of grass each day. A cow eats about 20 pounds. A cattleman will soon learn to
estimate pounds of lovegrass available per acre by keeping track of the hay he harvests.
By knowing the pounds of grass needed per animal and the pounds of grass available, the
winter stocking rate can be easily calculated.
Armyworms ate about half of the 1969 aftermath crop grown on our nitrogenfertilized pastures. The infestation was similar to that on new stands of small grain. No
other perennial grass was similarly damaged, including those in a similar stage of growth.
This indicates two things. First, aftermath of fertilized lovegrass is highly palatable to
armyworms—which indicates that it is a high-quality forage. Second, cattlemen should
use insecticides on lovegrass aftermath if armyworms are a threat.
Significantly, we have never had a snow that covered our lovegrass to the point
that we considered emergency feeding necessary. In contrast, we have fed hay when
snow covered the short grasses.
127
Winter Grazing on Yearlong-Grazed Lovegrass
Procedure: Pastures of lovegrass were grazed in winter, following summer
grazing, with an average of sixteen steers during each of five winters. The pastures were
grazed yearlong under extensive management, and thus were never fertilized, burned,
mowed, or maintained with a stubble barrier. Spot grazing was severe. The steers were
fed 2 pounds of cake per head daily during winter.
Results: Steers on yearlong-grazed lovegrass made nearly as much winter gain to
March 31 as did steers on yearlong-grazed native range. Steers on lovegrass gained 55
pounds per head, whereas steers on native range gained 67 pounds (Table 2).
The average yearlong stocking rate was 2.5 acres per steer on lovegrass, and 10.5
acres on native range. However, this period included two years of moderately severe
drought. During nondrought years, stocking rates were 2.0 and 9.0 acres.
The lovegrass pastures had much coarse, ungrazed forage on them at the end of
the winter. This “rough” interfered with subsequent summer grazing and should have
been removed.
Discussion: This program is not recommended. Stands cannot be maintained due
to spot grazing of the lovegrass. In addition, yearlong cattle gains are low.
Table 2. Winter Gain of Weaner Hereford Steers on Yearlong-Grazed Pastures of (1)
Weeping Lovegrass and (2) Native Range1
Winter
1946–47
1947–48
1948–49
1949–50
1950–51
Average
Daily gain
Lovegrass2
61
50
67
61
38
55
.41
1
Cake was fed at 2 pounds per head per day.
Data based on about seventeen steers per year.
2
128
Gain/Steer (Pounds)
Native Range
57
85
57
78
60
67
.50
Procedure: Duplicate pastures of lovegrass that had been rested summer-long
were grazed from about December 1 to March 31 with a total of thirteen steers during
each of six winters. Thus, at the start of grazing, each pasture had the full growth of
forage for the year. These pastures were not fertilized or mowed. The steers were fed 1.5
pounds of cake per head daily.
Results. Steers pastured during winter on summer-long rested lovegrass gained
slightly less than steers on yearlong-grazed native range, 36 and 47 pounds per steer,
respectively (Table 3). The steers ate the overmature, summer-rested lovegrass more
readily than they ate scattered plants of switchgrass (Panicum virgatum) and little
bluestem (Andropogon scoparius) growing in the same pastures.
The average stocking rate on lovegrass was .75 acre per steer. However, this rate
of stocking left much unused grass at the end of the winter. At the start of grazing, these
unfertilized pastures had 2,750 pounds of forage per acre on them, which would indicate
that the pastures could have carried a steer to each half-acre.
Table 3. Winter Gain of Weaner Hereford Steers Grazed on (1) Pastures of Weeping
Lovegrass Rested Summer-long and (2) Native Range Grazed Yearlong1
Winter
1959-60
1960-61
1961-62
1965-66
1967-68
1968-69
Average
Daily gain
Lovegrass
56
39
29
27
26
38
36
.30
Gain /steer (Pounds)
Native range
59
32
67
22
46
59
47
.39
1
Winters were from about December 1 to March 31. Lovegrass was stocked at .75 acres
per steer and native range at 8 acres per steer.
Feeding Overmature Lovegrass Hay
Procedure: Overmature lovegrass hay was fed to steers during three winter trials.
Each trial lasted about 100 days. The only feeds during these trials were hay and 11/2
pounds of cake per steer daily.
The first year, the hay was cut (dough stage) from ungrazed pastures planted the
previous year. During the next two years, the hay was cut from pastures grazed one or more
times before mowing, or when the grass was considerably more than forty days of age.
129
Results: Steers fed the overmature lovegrass hay made acceptable gains. During
the first trial when the highest quality hay was fed, the steers gained 80 pounds per head.
During the next two winters, the steers gained 60 pounds per head.
The steers ate about 11.5 pounds of hay per head daily the first winter when
quality was highest. During the following two winters, daily hay intake averaged only
8.5 pounds.
Discussion: We emphasize that the hay fed in this trial was not representative of
good-quality lovegrass hay. However, these results do show that overmature lovegrass
hay can be economically used.
Our careful observations, and those of many cattlemen, show that lovegrass hay
made when grass is young (about forty days old) is eaten readily and produces gains
similar to other high-quality hays.
Lovegrass offers much potential for highly profitable hay on upland sites because
of its excellent quality and high yields (21/2 to 4 tons per acre at Woodward).
The hay used in the trials reported here is representative of low quality hay that
would sometimes be taken from pastures that are in a grazing program. Although proper
timing of mowing is more difficult on pastures than on hayland, a cattleman should try to
harvest good quality hay from his pastures by mowing when lovegrass is not over forty
days old.
Supplements for Wintering Steers on Lovegrass
Procedure: Weaner steers were wintered on pastures of overmature lovegrass and
fed supplements at the following daily rates per steer: (1) 1.5 pounds cake; (2) 2.5
pounds cake; (3) 3.5 pounds cake; (4) 1.5 pounds cake plus 1.5 pounds milo; and (5) 1.5
pounds cake plus 3 pounds milo. The study was conducted in two replications from
about December 1 to March 20 (113 days) during three years. The pastures were rested
during the summers preceding the first two trials and grazed during the summer preceding the third trial.
Results: Gains were essentially related to the amount of protein fed. Steers fed
1.5 pounds of cake gained 30 pounds per head, those fed 2.5 pounds of cake gained 60
pounds, and those fed 3.5 pounds of cake gained 85 pounds (Table 4).
Feeding 1.5 pounds of grain per day in addition to 1.5 pounds of cake increased
total gain per steer only 5 pounds (Table 4). Feeding 3 pounds of grain per day in addition to 1.5 pounds of cake increased gain only 24 pounds per head. In comparison,
feeding 1 pound of additional cake above 1.5 pounds increased gain 30 pounds.
130
Table 4. Winter Gain of Weaner Hereford Steers Fed Three Daily Rates of Cottonseed
Meal (Cake) and Two Rates of Milo on Overmature Weeping Lovegrass1
Winter
Steers per
Treatment
1.5
1965-66
1967-68
1968-69
12
8
11
27
26
38
10
——
30
Three-yr. avg.
Daily gain
Cake/Steer (Lb.)
Cake + milo/Steer (Lb.)
2.5
3.5
1.5+1.5 1.5+3.0
Pound/steer
58
80
38
55
54
82
18
36
68
94
48
71
60
.27
85
.53
35
.75
54
.31
.48
1
Trials were from about December 1 to March 31. Approximate pounds of supplemental
digestible protein fed per day were 1.5 pounds cake, .5; 2.5 pounds cake, .8; 3.5 pounds
cake, 1.1; 1.5 pounds cake + 1.5 pounds milo, .6; and 1.5 pounds cake + 3 pounds milo,
.7.
Discussion: The most profitable level of caking on overmature lovegrass appears
to be 2 to 2.5 pounds of 41 percent protein cake per head per day. Contrarily, steers on
aftermath lovegrass made the same gain as steers on native range (54 pounds per steer)
when fed only 1.5 pounds of cake daily. We believe the gain responses of steers on
aftermath to the higher caking rates would be about the same number of pounds as on
overmature lovegrass. Feeding the higher rates of cake on aftermath would generally be
profitable if steers were sold at the end of winter and unprofitable, because of compensatory (catch-up) gains, if steers were sold at the end of summer.
Adding 1.5 pounds of grain to 1.5 pounds of cake was definitely unprofitable
when fed during winter on overmature lovegrass. Similarly, adding 3 pounds of grain to
1.5 pounds of cake was unprofitable at the prices of cake and grain prevailing in recent
years. We now speculate that the grain might have produced higher gains if protein had
been fed at a higher level—but actual data has not yet been obtained.
131
Q.
Is it feasible to overseed with vetch to be used to replace commercial protein
supplements?
A.
No, we are out of the vetch producing area at Woodward, at least for consistent
performance.
Q.
Does this work at Ardmore?
A.
No, vetch and weeping lovegrass green seasons are essentially the same under
good weeping lovegrass management. We may get some “picking” grazing on
vetch during winter, but it is not dependable. As a winter protein supplement, it
would not work. Winter small grain pastures are used as protein supplements
with dry grass roughage. There are numerous good programs of grazing green
small grain pastures and dry grass, both in overseeded and clean seedbed pastures.
132
Seed Production, Weeping Lovegrass
Eragrostis curvula (Schrad.) Nees, in Oklahoma
Robert M. Ahring
Research Agronomist, Crops Research Division
Agricultural Research Service
U.S. Department of Agriculture
Assistant Professor of Agronomy, Oklahoma State University
Weeping lovegrass, Eragrostis curvula, an introduced perennial grass, has persisted in some stands in Oklahoma for more than twenty-five years. Its seedling vigor,
ease of establishment, competitiveness with weeds, yield of forage under semiarid conditions, soil conservation value, and other desirable qualities have created a continuing
interest in the species.
Since weeping lovegrass generally produces one good seed crop each year, even
under dryland conditions, and because it is easily harvested, seed supplies are usually
adequate. However, few fields are established solely for seed production. The seed for
most of the acreage planted in Oklahoma comes from stands that are grazed, but which
may be managed and harvested for seed when prices are favorable.
From the jobbers’ standpoint, the stability and growth of a weeping lovegrass seed
production enterprise will not be feasible unless consumers demand certified seed of
improved strains.
At present, information on lovegrass seed production is furnished to growers
primarily by Soil Conservation Service personnel. The management and methods recommended are based on results of research (Staten and Elwell, 1944; Murphy et al., 1947;
Staten, 1949; Denman et al., 1953) and their own field experience.
Our experiments were designed for study of the influence of nitrogen and management on seed production of two strains of weeping lovegrass under irrigated conditions. The work was conducted at the Livestock Research Station near El Reno, Oklahoma.
Literature Review
The major part of the literature pertaining to seed production of weeping
lovegrass was published from 1940 to 1950. The fact that the species is an excellent seed
producer and seldom fails to make at least one good crop each year, regardless of general
climatic conditions, probably accounts for the lack of continued research.
Investigations of weeping lovegrass planted in three-foot rows, at seven locations
in Oklahoma, for seed production (Murphy, et al., 1947) revealed that response to nitro–
133
gen applications varied with location. Responses to forty-five to forty-eight pounds N
per acre ranged from .91 to 4.76 pounds of seed for each pound of actual N applied.
Phosphorus alone did not increase seed yields, but, in combination with nitrogen, produced the highest yields. Similarly, (Denman et al., 1953) found the addition of (fortyfive pounds P per acre) phosphorus and (ninety pounds N per acre) nitrogen produced
higher seed yields than nitrogen alone. Maximum yields of 238 pounds of seed were
reported. Phosphorus was of minor value when low rates of nitrogen were applied, but
became more important as nitrogen rates increased. Seed yields of 113 pounds have been
reported in Maryland, 320 to 450 pounds and 60 to 140 pounds under irrigated and
dryland conditions, respectively, in Oklahoma, and 580 to more than 1000 pounds per
acre (Crider, 1945) in Arizona.
Advantages cited for wide rows over solid stands for seed production (Garrison,
1960) were (1) smaller amounts of stock seed are required for planting (2) weed control
and roguing are simplified and (3) some species maintain high yields of seed for a longer
time. Seed production of weeping lovegrass (Staten and Elwell, 1944) planted in row
widths of 0 (broadcast), 21, and 42 inches produced an average of 62, 82, and 100
pounds of seed, respectively, per acre. Highest seed yields generally occurred under
dryland conditions with wide row spacing of 36 to 42 inches. However, the first year, in
species other than weeping lovegrass, comparative seed yields by row spacing are frequently highest from solid stands (Austensen and Peabody, 1964; Buller et al., 1955;
Klages and Starks, 1949). Row spacings of 6 to 8 inches or double-drilled 10 to 12
inches are considered solid stands (SCS State Standard Specification Code 512). Such
stands are often grazed in Oklahoma from about mid-April to May 10 when livestock are
removed and a seed crop is allowed to mature for harvest in July. Generally, yields are
low, varying from 40 to 150 pounds per acre, depending on the rainfall, fertility of the
soil, and management.
Materials and Methods
Approximately 1/4 acre tracts of weeping lovegrass P. I. 208-994 (Cv. ‘Morpa’)
and P. I. 232-813 were established in 1961 in rows 3 feet apart. The initial study utilized
four fertility treatments on each strain, i.e. (1) a control which received no fertilizer, (2)
60 pounds actual N per acre, (3) 30 pounds actual K per acre, and (4) 60 pounds N plus
30 pounds K actual per acre. The commercial fertilizers used to obtain these rates were
ammonium nitrate (33 percent N) and muriate of potash (49.8 percent K). Two replicates
of each treatment were arranged in a randomized complete block design. Each plot
consisted of four rows 5 feet long. Yield data were taken from the two middle rows in
each plot. The treatments involving potassium were discontinued in 1965.
Subsequent studies, 1967 through 1969, were conducted using four rates of
nitrogen, i.e. (1) a control which received no N, (2) sixty pounds, (3) 180 pounds, and (4)
360 pounds actual N per acre. All treatments in both studies were applied annually to
each of two crops. However, yields reported are from the first seed harvests. This study
134
was primarily intended to investigate seed set in the second (fall) seed harvest. Both
lovegrass strains failed to set seed in the fall crop. The effect of fertilization was measured by seed yields and the production of plant dry matter.
The management of each crop was the same. In early March, the residue from the
previous crop was burned. On alternate years, a blanket application of 20 pounds P per
acre was applied to the stands of both strains soon after spring burning. Nitrogen applications were made in April. Cultivations and irrigations were applied as needed. One-half
pint of 2,4-D per acre was applied when needed for the control of broadleaf weeds.
The summer seed crop matured in late June, at which time seed yield measurements were taken. The remainder of the seed crop was combine harvested, followed by a
mowing and baling operation to remove crop residue. In July, after the forage was removed, the plots were again fertilized, cultivated, and irrigated. The second seed crop
matured in September and October, but seldom in amounts that merited harvesting.
Two crops per year of weeping lovegrass seed are possible and occasionally are
harvested under Oklahoma conditions. Our observations indicate that the lack of seed set
in the fall crop is in part due to high nocturnal temperatures during July and August.
Diseases and seed-feeding insects that reduce seed yields in other forage plants do not
appear to present a problem in either the summer or fall seed crops of weeping lovegrass.
In five out of six years, seed yields were significantly greater where nitrogen was
a part of the fertility treatment as shown in Tables 1 and 2. In the initial study, plants of
plots receiving potassium alone matured seed a week or so ahead of plants fertilized only
with nitrogen. Reduced plant vigor, fewer seed stalks, and earlier seed maturity characterized the appearance of both control and K treatments when compared to N fertilized
plots. Although seed stalks were not counted, they appeared to be much higher in the
nitrogen treated plots of both strains. The response of P. I. 208-994 (‘Morpa’) and 232813 to nitrogen fertilization was similar. In general, seed yields produced by P. I. 208-994
were higher than P. I. 232-813. It was obvious from yield data and field observation that
nitrogen was the major nutrient needed for maximum seed production. This study was
discontinued after the first crop harvest of 1965. The experimental areas of both strains
were given a blanket application of 60 pounds actual N in addition to 48.9 pounds K (60
pounds K20) in July. No further treatment or study on the areas was made in 1966.
Prior to initiating the N fertilization study in 1967, soil samples were taken from
each previously treated plot and bulked by treatment. Analyses of these samples showed
a very high content of available P and K. The soil type (Brewer clay loam) on which both
stands were established contained 190 to 260 pounds available P, 645 to 915 pounds
available K, and less than 10 pounds nitrate-nitrogen per acre.
135
Seed yields of P. I. 208-994 (‘Morpa’) were significantly increased by the application of 60 pounds N per acre each year, 1967, 1968, and 1969. Furthermore, there were
significant differences in seed yields for level of N in all three years. Yields were reduced when N rates were increased to 180 and 360 pounds per crop per acre. The results
suggested that weeping lovegrass seed yields are best when 60 to 90 pounds of N per acre
are applied in April. Nitrogen rates above 90 pounds N retarded early plant growth at
both application dates (April and July) and significantly reduced seed yields.
Nitrogen fertilization gives similar responses in P. I. 232-813. However, a slightly
higher nitrogen rate appears to be necessary to attain a yield comparable to that of P. I.
208-994. Differences between rates of N were not significant in two of three years of
study. Seed yield response from plots fertilized with 180 and 360 pounds N in 1969 was
significantly higher than the control and 60-pound N treatments.
Both strains of weeping lovegrass produced two harvestable seed crops in 1968.
This was the first crop to merit harvesting in eight years. A combination of unusually
humid weather in July and August with cool night temperatures, followed by drier
weather and cool nights in September, may have created a favorable environment for seed
set in the fall crop.
Forage yields were harvested by fertilizer treatments in conjunction with both
seed crops, Table 3, in 1968 and 1969. No differences existed in the amount of plant dry
matter produced between nitrogen rates for either harvest during both years of study.
Sixty pounds actual N per acre produced, in general, as much dry matter per acre as either
of the other levels. However, all N levels significantly increased the amount of plant dry
matter produced.
Different methods of removing field residue were not compared before resumption of spring growth on seed yields. However, field burning of weeping lovegrass, if
soil moisture is present, does not injure the stand and may have certain advantages over
mechanical removal, such as (1) complete residual removal (2) increased effectiveness of
nitrogen fertilization (3) aid in the control of weeds, insects, and diseases or (4) tendency
to produce more early and uniform growth.
Summary and Conclusions
Occasionally two crops per year of weeping lovegrass seed can be harvested
under Oklahoma conditions. If properly managed and irrigated, the summer crop harvested in June will produce an average of 400–500 pounds of seed per acre. The fall crop
matures in September, but seldom sets seed in amounts that justify harvesting.
The management of each field consisted of (1) burning the forage residue of the
previous fall in early March, (2) application of fertilizer in April, and (3) cultivation and
irrigation as needed. After the summer seed crop harvest, the remaining vegetation is
mowed and baled. In July, when the forage removal operation is complete, the fields are
136
again fertilized, cultivated, and irrigated. Although these management practices are
highly successful for the production of good to excellent summer seed crops, they are
inadequate for the fall crop. Removal of the remaining vegetation after the first seed
harvest, if delayed until mid-August, may be a better practice for fall seed production.
There are no apparent reasons why the fall seed crop should fail to set seed, other than
day length and unfavorable night temperatures during heading and maturity as possibilities.
Maximum seed yields in these investigations were obtained with an application of
60 pounds actual N per acre per crop harvest. The soil was high in available phosphorus
and potassium. Soils deficient in these elements should be fertilized with rates suggested
by soil tests.
Table 1. Average Seed Yields of P. I. 208-994, ‘Morpa’, Weeping Lovegrass by Treatment over a Six-Year Period of Study
2
N1
Treatments, Lb./Acre1
K1
N2
N2K1
N3
N4
Year
Crop
1963
1964
1965
(3 yr.)
1
1
1
276
313
313
301
334
313
281
309
247
484*
357
363
290
442*
382*
371
—
—
—
—
—
—
—
—
1967
1968
1
1
2
372
471
10
481
—
—
—
514*
414
139*
553*
—
—
—
463
350
87
437
441
359
45
404
1969
1
181
—
543*
—
430
539*
344
—
536
—
443
461
Study 1
Avg.
Study 2
Avg.
(3 yr.)
*Significant at the .05 level of confidence.
1
K1 = 30 lbs. actual K per acre, N1 = Control, N2K1 = 60 lbs. N plus 30 lbs. K per acre, N2
= 60 lbs. actual N per acre, N3 = 180 lbs. actual N per acre, N4 = 360 lbs. actual N per
acre.
2
1 = summer seed harvest (June).
2 = fall seed harvest (September).
137
Table 2. Average Seed Yields of P. I. 232-813, Weeping Lovegrass, by Treatment over a
Six-Year Period of Study
Year
Crop1
N1
K1
N2
N2K1
1963
1964
1965
1
1
1
225
177
148
312
153
186
261
350*
339*
211
378*
384*
—
—
—
—
—
—
183
217
283
324
—
—
N3
N4
Study 1
Avg. (3 yr.)
Study 2
1967
1968
1
1
2
236
472
6
478
—
—
—
472*
469
86*
555
—
—
—
463*
412
73*
485
482*
496
59
555
1969
1
92
—
376
—
466*
424*
268
—
468
—
471
487
Avg. (3 yr.)
1
K1 = 30 lbs. actual K per acre, N1 = Control, N2K1 = 60 lbs. N plus 30 lbs. K per acre, N2
= 60 lbs. actual N per acre, N3 = 180 lbs. actual N per acre, N4 = 360 lbs. actual N per
acre.
2
138
Table 3. Average Yields of Plant Dry Matter Produced by Two Weeping Lovegrass
Strains at Two Different Harvest Dates under Various Levels of N Fertility over a TwoYear Period of Study
Strain (P. I.)
Year
Crop2
N1
N2
N3
N4
208-994
Cv. ‘Morpa’
1968
1
2
1.80
.80
2.60
2.30
1.50
3.80*
3.20
1.30
4.50*
2.20
1.60
3.80*
1
2
1.09
1.27
2.36
2.22
1.94
4.16*
2.07
2.50
4.57*
2.38
1.95
4.33*
2.48
3.98
4.53
4.07
1
2
2.60
1.80
4.40
3.70
1.20
4.90*
3.20
1.10
4.30
3.10
1.30
4.40
1
2
.38
1.01
1.39
1.86
2.40
4.26*
2.30
2.90
5.20*
2.59
2.40
4.99*
2.89
4.58
4.75
4.69
Total
1969
Total
Avg.
(2 yr.)
232-813
1968
Total
1969
Total
Avg.
(2 yr.)
1
N1 = control, N2 = 60 lbs. actual N per acre, N3 = 180 lbs. actual N per acre, N4 = 360
lbs. actual N per acre.
2
139
Literature Cited
Austensen, H. M. and Dwight V. Peabody, Jr. 1964. Effects of row spacing and time of
fertilization on grass seed production. Agron. J. 56:461-463.
Buller, Roderic E., J. S. Bubar, H. R. Fortmann and H. L. Carnahan. 1955. Effects of
nitrogen fertilization and rate and method of seeding on grass yields in Pennsylvania. Agron. J. 47:559-563.
Crider, Franklin J. 1945. Three introduced lovegrasses for soil conservation. USDA
Circ. 730.
Denman, C. E., W. C. Elder and V. G. Holler. 1953. Performance of weeping lovegrass
under different management practices. Okla. Agri. Exp. Sta. Tech. Bull. T-38.
Garrison, C. S. 1960. Technological advances in grass and legume seed production and
testing: I. Maintaining varietal purity and cultural and management practices.
Advance. Agron. 12:42-71.
Klages, K. H. W., and R. H. Stark. 1949. Grass and grass seed production. University of
Idaho Agr. Exp. Sta. Bull. 273.
Murphy, H. F., H. W. Staten and W. C. Elder. 1947. The effect of fertilizer on grass seed
production. Okla. Agr. Exp. Sta. Bull. B-319:85-90.
Staten, H. W. 1949. Weeping lovegrass for the Southwest. Crops and Soils. 2(2):18-21.
Staten, H. W. and Harry M. Elwell. 1944. Weeping lovegrass in Oklahoma. Okla. Agr.
Exp. Sta. Bull. B-281.
Q.
How long can you graze during early spring without damaging the seed crop?
A.
Staten, in previous work, suggested that grazing could be done until May 10 (in
central Oklahoma). At this time, grazing would be deferred to allow a seed crop
during late June. I think yields would be reduced. For a seed crop, I would defer
all spring grazing and harvest hay after a seed harvest.
140
An Example of Weeping Lovegrass in a Diversified Farming Program
Bob Drake
Drake Brothers Farms
Davis, Oklahoma
We farm and ranch on the “sunny side” of the Arbuckle Mountains in the Murray
County area. Basically, our operation is a cow-calf operation. We have commercial and
registered cattle and do some crossbreeding. In addition to the cow herd, we have a
stocker program which was developed with assistance from Noble Foundation people. It
begins around November on small grain pastures and ends sometime in June, depending
on the weather.
Drake Farms is a partnership between my brother, mother, and myself. In 1964,
we started cooperating with the Noble Foundation. They took a complete survey of our
ranch, took soil samples, looked at native pastures, etc. They found we had gravelly soils
that were not the best for growing pastures. We were encouraged when they said it could
be improved with a little bit of management and labor—and a lot of money. In addition
to the problem we had with some of our soils, we also had a timber problem. Two-fifths
of our land was in timber. Our original work dealt with a 505-acre pasture in the center
of the ranch, which contained 255 acres of timber and grass and 210 acres of fair condition bluestem. We also had 20 acres of bermudagrass. The pasture had an annual carrying capacity of forty-nine animal units (forty-nine cows with calves or 10.3 acres per
cow), and it didn’t run this forty-nine real well. Noble Foundation personnel recommended starting first with the open area pastures, rather than clearing any timber, since
these pastures could be improved considerably cheaper than the timbered areas.
In 1964 and early 1965, Noble Foundation personnel began talking to us about
weeping lovegrass, but in the cafes of Davis or Ardmore, when we mentioned this to
people, they laughed at us. Weeping lovegrass! No one we talked to had ever heard of it
working. It was foolish—it didn’t make anything but good bedding. Cattle wouldn’t eat
it, and all you could do was burn it off. So consequently, we vetoed the idea and went to
the bermudagrass. We bought a two-row sprigger and began sprigging12 to 15 bushels of
Midland bermudagrass sprigs per acre. We topdressed in June following the recommendations that the Noble Foundation made. The weeds in the bermudagrass were sprayed
the first year. Where we got a good spray job, we got a good bermudagrass stand, so it
really does pay to spray.
In 1966, we began a clearing program. To save money, we thought we would try
to do the clearing ourselves. We mounted a Waldon blade on a 4020 tractor, put a bar on
it, and tried to push the scrub timber. It worked pretty well, but the expense was too
great. We couldn’t get over it fast enough, so a dozer was hired to come in and start
clearing. The dozer had a cutter bar on the blade, and asked if we would let him try it. It
was pretty much an experiment for him in our area. We gave him 20 acres of second
growth timber to run over, and he did run over it. He pushed it fast, and the cost was
141
about $20 per acre. He was cutting about 1 to 2 inches below the ground. This didn’t
work very well, because we discovered later that there was a tremendous sprout problem.
The same year in late October, we bought our own dozer. We found this to be the most
satisfactory method for us to clear timber. If the dozer had to sit, the operator could weld
or do something else. After the clearing, we started cleaning up and burning brush piles.
Our method of burning was using a flame torch mounted on a 250-gallon propane tank.
The torch will throw a flame approximately 10 feet, and brush piles can be set on fire as
fast as a man can walk. Before, we had been using diesel oil and tires, but this was too
slow. The torch costs about $65 to $75, and you can get one at most propane dealers. It
is the most economical and efficient method we have found.
In 1967, we finally gave in to the Noble Foundation. We came down to one of the
field days, saw their lovegrass, and decided to try some. Knowing it wouldn’t work, we
just planted it more or less to satisfy them. We put it in a pasture that also contained
native grass and bermudagrass with the thought that, if it works here, it will work anywhere. We followed their recommendations of using 1.5 to 3 pounds of seed per acre,
plowing down 200 pounds of 0-20-20, and following a nitrogen topdressing. It was
planted with a brillion seeder. The brillion seeder didn’t work too well because the
sprouts and rough ground tore it up. We were amazed when checking cattle in May and
June of that same year. The cattle had access to lush bermudagrass and native grass
pastures, but 90 percent of the time, we found them on the 20 acres of lovegrass. They
literally ate it into the ground. We never took the cattle off until the middle of July and
almost lost our stand. We had adequate rainfall, the grass was tender, and we got tremendous grazing off of it. The following year, we decided to prepare another 100 acres. We
had a real wet year in 1968 and were able to plant only 30 acres. Again, it was planted on
cleared timberland that had an erosion problem. We used several planting methods, and I
can tell you that it can’t be put through the grain box on a grain drill. We planted enough
seed on 30 acres to sow 100 acres. We got a tremendous stand, but it was a little expensive. An easy flow was used the same year, and we had no more luck with it than with
the drill. In 1969, the remaining area was planted to complete the 100 acres. We found
that a small seed attachment on a grain drill was adequate for planting lovegrass. Four
pounds of seed per acre is best for our area.
We had some problems with our 1968–69 planting of lovegrass. Heavy rains
came and caused erosion before the grass took hold. In addition, sprouts were all over
the field; we couldn’t take care of the sprout problem due to the erosion problem. The
ground is still too rough and will tear up machinery. Bermudagrass was sprigged within a
three-week period in a field adjacent to the lovegrass. There was very little erosion or
sprout problem on the bermudagrass area. We feel we can’t use lovegrass on cleared
timberland that is subject to erosion.
Costs involved in developing this land to lovegrass and bermudagrass are shown
in Table 1.
142
Table 1. Per Acre Operation Costs to Establish Improved Grasses on the Drake Farms
Clearing
Cleaning
Seedbed
Fertilizer
Planting
Weed control
Total
Lovegrass
25.00
13.00
13.50
5.60
3.60
2.00
$62.40
Bermudagrass
25.00
13.50
13.50
5.60
9.00
2.00
$68.10
Clearing second growth timber cost us $25.00 per acre. A commercial operator can do
this much cheaper because they can move faster. However, with our own dozer, we get
all the stumps out. Clearing cost us $13.00 per acre. This involved picking up two or
three times over the field and burning. We want our land in good enough shape to farm if
needed. Fertilizer cost $3.60 per acre for both grasses. Again, we used the Noble
Foundation’s recommendation of 18-46-0 applied as a starter fertilizer. It is cheaper to
sow lovegrass than sprig bermudagrass. We used weed control on lovegrass the first year
because of a weed problem. We let an airplane do all our weed spraying for us. We had a
$62.40 total per acre cost on lovegrass and $68.10 on bermudagrass. We feel like these
are accurate figures. When the pastures were completed, we had a real smooth pasture,
other than the one patch of lovegrass that had an erosion problem.
Once you get lovegrass established, the most important thing is management. In
our 1968 planting, we didn’t turn in enough cattle, and the stuff got away from the cattle
before we knew it. It was too high, and the cattle walked off and left it. It made a good
bed, and, just as the old timers were telling us, that’s all it was good for. It was our fault
and not the fault of the grass. Across the road in the same pasture was the 50 acres we
established in 1969. The cattle ate it into the ground. This proves that when you have
this kind of grass, you must have the cattle in there to utilize it, or it is no good.
On March 10, 1970, we burned our lovegrass. As soon as we could get in after
the burning, we applied 175 pounds of ammonium nitrate per acre. On April 13, we
turned in 100 cows, three bulls, and ninety calves on 80 acres of lovegrass. The grass
was around 2 to 5 inches high. Really, the 2-inch grass was too short to graze, but I
called Noble and told them we had some growth of 5 or 6 inches and were afraid we
would get into the same conditions we got into last year. We went ahead and turned the
cattle on the lovegrass, bringing them from a bermudagrass pasture where we had been
creep feeding them. Most of the calves were fall calves and were eating 4 to 5 pounds of
creep per day. The feed was fed free choice, giving them all they could eat. Within two
days after turning the calves on the lovegrass, they were eating no creep feed, and we
didn’t have to put out any more. This indicated to us that the calves had to be getting
something from the grass to take care of the creep feed. By April 16, our overseeded
vetch-bermudagrass was able to carry one 850-pound Holstein steer per acre. At the
same time, our straight bermudagrass was not furnishing any grazing. We had one
143
patch of lovegrass that we couldn’t burn because of high wind. Because it was not burned,
it was a week or ten days behind the pasture we burned. The only management difference
was the burning. It was fertilized the same date, receiving 200 pounds per acre. Cattle
seemed to prefer the native grass over the lovegrass with the old growth on it.
The production on the 505 acres after improvements is shown in Table 2.
Table 2. The Annual Carrying Capacity on the Drake Farms after Improving Pastures
Acres
Timber and grass mixed
Lovegrass
Bluestems
Bermudagrass
Summer fallowed
1968
30
100
20
50
200
Carrying capacity
Acres/cow
24 AU
8.0
North Field
1969
80
100
20
200
49 AU
4.1
South Field
1968
1969
155
105
150
200
305
305
51 AU
5.9
82 AU
3.7
The 505 acres were divided into a north field containing 200 acres and a south
field containing 305 acres. In 1968, the north field was stocked with one animal per 8
acres. This is high because we were not able to plant 50 acres of lovegrass. In 1969, it
was planted, and we lowered the acres per animal unit down to 4.1. In the south field, we
still have some timber. In 1968, the acres per animal unit on bermudagrass was 5.9. In
1969, we cleared more timber and sprigged bermudagrass and were able to lower our
acres per animal unit to 3.7. We hope to get down to 2.5 acres per animal unit by using
more lovegrass and bermudagrass and doing some rotational grazing.
Anytime you have improved pastures, you are going to have a maintenance
problem and an expense every year. If you don’t have any expense, you are not going to
have any grass. You might as well have native grass pasture. Our annual maintenance
costs for lovegrass and bermudagrass are shown in Table 3.
144
Table 3. Annual Maintenance Costs on the Drake Farms for Lovegrass and
Bermudagrass Pastures
Topdressing
Burning
Weed Control
Dragging
Total
Prorated development costs (10 yr.)
Total costs
Lovegrass
$ 6.75
.40
. . 7.15
6.24
$13.40
Bermudagrass
$ 4.25
. 1.00
1.00
6.25
6.81
$13.06
Topdressing lovegrass two times cost $6.75 per acre. A heavy application is
applied in early spring and another light application in early summer. The $6.75 is not
representative of most years. Ammonium nitrate has been selling for around $42.00 to
$43.00 per ton, and, as you know, it normally sells much higher than this. We put one
ammonium nitrate application on bermudagrass between May 1 and May 15, and, if
rainfall allows, we may topdress again in August.
Burning involves men and fire fighting equipment. We charge $0.40 per acre for
burning lovegrass. We have had to use weed control ($1.00 per acre) about every two
years to control annual broomweed. On our bermudagrass, we concentrated a few more
cattle and had to break up chips each year. Dragging costs about $1.00 per acre. The
establishment cost for lovegrass and bermudagrass is prorated over a ten-year period. We
have had bermudagrass for twenty to thirty years and haven’t had any problem with a
stand. Our total annual maintenance cost for lovegrass was $13.40 and for bermudagrass
was $13.06.
Our income for before and after improvements is shown in Table 4.
Table 4. Income per Acre on the Drake Farms before and after Pasture Improvements
Before improvement—90 Percent Calf Crop
Acres/animal unit—10.30
Return/acre to land, management, and capital—$9.79
After improvement—88 percent calf crop
1968 1969
North Field
Acres/animal unit
Return/acre to land, management,
and capital
8.00
4.10
$9.02 18.61
145
1968 1969
South Field
5.90
3.70
$10.94 19.81
Before we started improvement, we had a 90 percent weaned calf crop, which is
not real good, but not real bad. Our cows are pregnancy tested, but we always lose a calf
or two. Before improving our pasture, we had 10.3 acres per cow and a $9.79 return to
land, management, and capital. After the improvements on the north field in 1968, we
had a return of $9.02. This was increased to $18.61 in 1969 due to lovegrass going in. In
the south field, where we had bermudagrass, our return to land, management, and capital
was $10.94 in 1968 and $19.81 in 1969. This isn’t going to make any rancher rich, and it
won’t pay for land at current prices, but it is a lot better than we started with. However,
we are very pleased with these figures. We hope to increase our return at least another
$9.00 or $10.00. We are not sure we can, but we will know in another year or two.
Lovegrass can be used in a number of different ways. You can bale it or use it for
seed, but we think the most profitable method for us is using it with cows and calves.
Q.
How often do you burn?
A.
Once a year, March 1 to 15. We plan to burn every year even if there isn’t much
residue. We were able to get on these burned areas a full week before other low
residue areas.
Q.
Does burning help control the sprouts?
A.
We had hoped so, but it didn’t. This year, where we had a large residue, the fire
moved very fast and only bleached the sprouts a little. They are growing well
now.
Q.
Could you aerial spray sprouts?
A.
There isn’t enough problem in this area. In other areas, we haven’t gotten good
results on sprouts.
146
Effect of Fertilizer and Clipping Frequency on Weeping Lovegrass1
Jerold Lee Rogers, Soils Fertility Specialist
The following excerpts of information are from a thesis written by the author. It
is thought that the information contained herein could be helpful in understanding the
effects of fertilizers and clipping frequencies on weeping lovegrass. Although the experiments were compiled to supply information for highway departments in use of the plant
to control soil erosion, much of the information could be applied to establishing and first
year utilization practices of weeping lovegrass. A complete copy of the thesis can be
obtained on loan from the University of Arkansas library, Fayetteville, Arkansas.
Materials and Methods: A field test was initiated to study the effects of fertilizers
and clipping frequencies on establishment and growth of weeping lovegrass and its
ability to control soil erosion on highway rights-of-way.
In January 1968, a site was chosen in northeastern Arkansas for the field test. The
test area was two miles south of Strawberry in Lawrence County, along the east
backslope of State Highway 25.
The soil at the Strawberry test site was classified as a Cane fine sandy loam on a
40 percent slope. Soil test data are given below for the soil.
Soil
Cane fine sandy loam
pH
6.8
%
O. M.
0.8
P
7
Pounds per Acre
K
Ca
140
1140
Two replications of a factorial treatment set were used in a randomized complete
block design. Treatments for the study were three starter fertilizer levels, three nitrogen
topdressing levels, and three clipping frequencies.
Starter fertilizer levels were 0, 400, and 800 pounds per acre of 10-20-10 granular
commercial fertilizer. It was broadcasted on the soil surface and worked in before planting. Monthly nitrogen topdressing levels of ammonium nitrate were 0, 20, and 40 pounds
per acre of actual nitrogen from 33.5-0-0. Total nitrogen from 33.5-0-0 in these treatments was 0, 80, and 160 pounds per acre.
On April 18, 1968, the test area was prepared by disking. The starter fertilizers were
applied to the 10-x-20-foot plots. Weeping lovegrass seed was broadcasted at the rate of 10
1. This information was not presented at the symposium.
147
pounds per acre and then harrowed in. A wheat straw mulch was applied by hand at the rate
of 2 tons per acre.
Monthly nitrogen topdressings were broadcasted on May 29, June 22, July 25,
and September 5, 1968. A rotary mower was used to clip the plants to a 4-inch height.
On October 11, 1968, the plots were rated for soil erosion. Soil erosion was based
on the visual amount of rill and/or sheet erosion in each plot. A scale of 0 to 10 was used
with a value of 10 being severe erosion and a value of 0 being no erosion. Plots were
rated by two individuals and converted to percent, and averaged values were converted to
arcsin for statistical analysis.
Percent ground cover and top weights were taken on October 26, 1968. Percent
ground cover in each plot was taken by the point frame method with ten random sets of
ten points. Percent values for ground cover were converted to arcsin for statistical analysis. Top weights were taken by mowing a 11/2-x-20-foot strip from each plot. The clippings were dried and weighed.
An analysis of variance was performed on the data for top weights, ground cover,
and soil erosion. Single degree of freedom comparisons were used to determine differences between treatments’ means. Differences discussed were significant at the 5 percent
level of probability.
Results and Discussion: The effects of starter fertilizers on top weights of weeping lovegrass are presented in Table 1. Starter fertilizer resulted in an increase of top
weights in comparison to the unfertilized treatment. There was no difference in top
weights between starter fertilizer treatments. This differs from the results obtained from
the greenhouse test where there was a significant difference between the two starter
fertilizer treatments. It should be noted that, in the greenhouse test, adequate water was
provided throughout the growing period, and roots were restricted to a smaller volume of
soil. This would indicate that the lack of adequate moisture, increased soil volume, or
possibly some other factor may have limited the response to starter fertilizer under field
conditions.
The effects of monthly applied nitrogen on top weights of weeping lovegrass are
presented in Table 1. Nitrogen applied at 80 or 160 pounds per acre resulted in an increase in top weights in comparison to treatments that received no nitrogen. Top weights
were greater from the 160 pounds per acre treatments than from the 80 pounds per acre
treatment. These results agree with those obtained in the greenhouse study and also with
those of other investigators where top weights of weeping lovegrass increased with
increasing increments of nitrogen fertilizer. Since significant increases in top weights
were obtained from increased levels of nitrogen, this would indicate that nitrogen was a
limiting factor for growth of weeping lovegrass on this soil.
Top weights of weeping lovegrass as influenced by different clipping frequencies
are shown in Table 1. Clipping at a frequency of either four or eight weeks reduced top
148
weights in comparison to the unclipped treatment. The reduction in top weights was
greater at the four-week interval than at the eight-week interval. These results agree with
those obtained in the greenhouse study and also with the results of other workers where
top weights decreased proportionately with increasing clipping frequencies.
Table 1. Top Weights of Weeping Lovegrass As Influenced by Different Rates of Fertilizer, Nitrogen Fertilizer, and Clipping Frequencies
Starter fertilizer (lbs./acre)
0
40-80-40
80-160-80
Actual nitrogen (lbs./acre)
0
80
160
Clipping frequencies in weeks
Unclipped
8
4
Dry top weight (lbs./acre)
736
1875
1898
979
1491
1958
1155
1500
1856
The effects of starter fertilizer and nitrogen fertilizer on top weights of weeping
lovegrass are given in Table 2. Top weights in the treatment which received no starter
fertilizer increased when 80 pounds per acre of nitrogen were applied, but decreased
when 160 pounds per acre were used. There was no apparent explanation for this decrease in top weights. Top weights were greater with 40-80-40 pounds per acre of starter
fertilizer and nitrogen topdressed than with 80-160-80 pounds per acre and nitrogen
topdressed. This would indicate that, when nitrogen is used, the lower rate of starter
fertilizer is sufficient for maximum growth in this soil.
The effects of starter fertilizers and clipping frequencies on top weights of weeping lovegrass are presented in Table 3. Starter fertilizer increased the top weights of
weeping lovegrass in all clipping treatments. Top weights at the eight-week interval were
greater with the lower rate of starter fertilizer than in the higher rate. This would seem to
indicate that at the eight-week clipping interval, the lower rate would be sufficient. At the
four-week clipping interval, the higher rate of starter fertilizer gave the greatest top
weights. This would indicate that, as clipping frequencies increase, there is a response to
higher rates of starter fertilizer.
Table 2. Top Weights of Weeping Lovegrass As Influenced by Different Rates of Starter
and Nitrogen Fertilizer (Lbs./Acre—Dry Weight)
Starter Fertilizer
Lbs./Acre
0
40-80-40
80-160-80
Actual Nitrogen (Lbs./Acre)
0
80
160
509
899
803
1021
1987
2618
1411
1830
2452
149
Table 3. Top Weights of Weeping Lovegrass As Influenced by Different Rates of Starter
Fertilizer and Clipping Frequencies
Clipping Frequencies
(in Weeks)
Unclipped
8
4
0
790
854
566
Starter Fertilizer (Lbs./Acre)
40-80-40
80-160-80
2278
2499
2038
1606
666
1590
The effects of starter fertilizer on ground cover of weeping lovegrass are shown in
Table 4. Ground cover was greater in fertilized treatments than in treatments that received no starter fertilizer. There were no significant differences in percent ground cover
between the starter fertilizer treatments. The lack of a difference in ground cover between the starter fertilizer treatments agrees with the results obtained from the top weight
data. Although there were no differences in percent ground cover between the two
fertilized treatments in the first year of growth, this does not necessarily mean that this
trend would continue in the following growing seasons.
Percent ground cover of weeping lovegrass as influenced by monthly applied
nitrogen is presented in Table 4. There was a greater percent ground cover in the nitrogen
topdressed treatments than in treatments with no nitrogen. There were no significant
differences in ground cover between the 80 and 160 pounds per acre treatments. These
results disagree with those obtained in the top weight data of the field study where there
were differences between the two nitrogen rates. This would be explained by plants
being heavier, but not necessarily providing more ground cover.
Table 4. Percent Ground Cover of Weeping Lovegrass As Influenced by Different Rates
of Starter Fertilizer and Nitrogen Fertilizer
%
Ground Cover
82
96
97
0
80-40
80-160-80
Actual nitrogen (lbs./acre)
0
80
160
85
95
96
The effects of starter fertilizer and monthly nitrogen fertilizer on ground cover of
weeping lovegrass are presented in Table 5. Ground cover was greater in treatments of
starter fertilizer and nitrogen than treatments of starter fertilizer alone, nitrogen alone, or
none of either. This trend was similar to the one observed for top weights.
150
of Nitrogen Fertilizer and Clipping Frequencies
Starter Fertilizer
(lbs./acre)
0
40-80-40
80-160-80
Actual Nitrogen (lbs./acre)
0
80
160
70
89
87
91
98
100
92
99
100
The effects of monthly nitrogen fertilizer and clipping frequencies on percent
ground cover of weeping lovegrass are presented in Table 6. Clipping at either interval
reduced ground cover in the treatments that received no nitrogen topdressing. There were
no reductions in ground cover due to clipping in the nitrogen topdressed and clipped
treatments.
of Nitrogen Fertilizer and Clipping Frequencies
Clipping Frequencies
(in Weeks)
Unclipped
8
4
Actual Nitrogen (Lbs./Acre)
0
80
160
90
94
94
79
97
97
85
95
95
The effects of starter fertilizer on soil erosion are shown in Table 7. There was
less soil erosion in starter fertilizer treatments than in treatments of no starter fertilizer.
There were no differences in soil erosion between starter fertilizer treatments. These
results follow the trends obtained for top weights and percent ground cover where there
was no difference between starter fertilizer levels, but there was a difference in fertilized
and unfertilized treatments. It could be assumed that erosion of soil in these treatments is
in proportion to the amount and intensity of ground cover provided.
The effects of monthly nitrogen fertilizer on soil erosion are presented in Table 7.
Soil erosion was less on nitrogen topdress treatments than in treatments of no nitrogen.
There were no differences in soil erosion between the 80 and 160 pounds per acre nitrogen treatments. The trend of decreased soil erosion as nitrogen levels increased is similar
to the results obtained for soil erosion of starter fertilizer treatments. Therefore, it might
be assumed that increased top weights and increased ground cover caused by nitrogen
fertilizer decreased the soil erosion.
151
Table 7. Soil Erosion in Weeping Lovegrass Sod As Influenced by Different Rates of
Starter Fertilizer and Nitrogen Fertilizer
0
40-80-40
80-160-80
Actual Nitrogen (lbs./acre)
0
80
160
Soil Erosion Rating*
3.6
.9
.4
2.6
1.0
.8
*Soil erosion was rated on the following scale: 0–3, slight, 3–6, moderate, and 6–10 severe.
Summary and conclusions: In 1968, a field experiment was conducted at a site
near Strawberry, Arkansas, to study the effects of different fertilizer rates and clipping
frequencies on the establishment and growth of weeping lovegrass. Three levels each of
starter fertilizer, monthly nitrogen fertilizer, and clipping frequencies were used alone and
in all combinations. The results of this experiment can be summarized as follows.
In the field experiment, top weights were found to respond similarly to those in
greenhouse study with the exception that there was no additional increase in top weights
of the 80-160-80 pounds per acre treatment over the 40-80-40 pounds per acre treatment
of starter fertilizer. Percent ground cover and soil erosion followed the same trends as
those obtained for top weights. This further substantiates the value of proper management practices to prevent costly soil erosion on highway rights-of-way.
These data indicate that, with no clipping, 40-80-40 pounds per acre of starter
fertilizer and four monthly applications of nitrogen at 40 pounds per acre (to equal 160
pounds) were sufficient for establishment and maintenance of weeping lovegrass for the
first season of growth. In treatments that were clipped periodically, additional amounts
of starter fertilizer are required for maximum growth. In all cases, however, growth of
weeping lovegrass was reduced when it was clipped.
152
Weeping Lovegrass for Vegetating
Strip-Mine Spoils in Appalachia1
Willis G. Vogel
Northeastern Forest Experiment Station
Forest Service, U.S. Department of Agriculture
Berea, Kentucky
Abstract
Weeping lovegrass is useful for vegetating strip-mine spoils in Appalachia because it produces quick cover on a wide range of spoil conditions. It is more tolerant of
extremely acid spoils (pH 4.0–4.5) and of dry sites and summer growing conditions than
most of the commonly used cool-season grasses and legumes. Although relatively shortlived, it works well in mixtures with slower-developing, long-lived grasses and legumes.
It provides the desired quick cover during the first growing season, but does not crowd
out the companion species, which usually obtain dominance by the third growing season.
When sown with direct-seeded black locust, lovegrass is less competitive with the locust
seedlings than are the oft-used cool-season grasses. Nitrogen and phosphorus fertilizers
are needed for establishing quick cover of lovegrass on many Appalachian coal-mine
spoils.
In the humid eastern United States, strip-mining for coal forms spoil banks that
pose problems of erosion, sedimentation, aesthetics, and land use. In the Appalachian
region, erosion and sedimentation are especially troublesome because much of the disturbance due to stripping occurs on steep mountain slopes. Thus, it is essential that, when
the mining disturbance is over, a cover of vegetation be established as quickly as possible
to stabilize the spoil surface and minimize runoff and erosion.
Success in establishing vegetation on mine spoils is related to the chemical and
physical characteristics of the various geologic materials that make up the spoil. Extreme
acidity, high content of soluble salts, and infertility cause revegetation problems on some
spoils. Although rainfall in Appalachia is usually abundant, physical characteristics of
some spoils cause desertlike microenvironmental conditions that adversely affect seed
germination or seedling growth.
Reforestation is often the long-term goal in mine-spoil reclamation, but a quickly
established cover of herbaceous vegetation is usually needed to provide immediate and
short-term site protection. Weeping lovegrass (Eragrostis curvula) has proved useful for
vegetating roadsides and eroded lands in the southern part of the United States. The
purpose of this paper is to present results of studies involving the use of weeping
lovegrass for vegetating strip-mine spoils in eastern Kentucky and other Appalachian
states.
153
Methods and Materials
Three types of experiments were conducted with weeping lovegrass: (1) speciesadaptation trials, (2) herbaceous mixtures; and (3) competition with seeded black locust.
Species-Adaptation Trials
Field plots: Field plots have been established every year since 1964 to evaluate
numerous herbaceous species for their capacity to produce cover on strip-mine spoils
with a wide range of chemical and physical characteristics. Weeping lovegrass has been
included each year. Species success was evaluated in terms of percent ground cover
(percent of the plot area covered by the vertical projection of foliage to the ground).
Ability of a species to provide quick cover was evaluated by estimating percent ground
cover at the end of the first growing season.
Most species were sown in early spring. Plots seeded in late winter or very early
spring often needed no seedbed preparation because frost action loosened the soil. However, plots seeded a little later usually needed to be tilled or harrowed before seeding.
After two years, it became obvious that fertilizer was needed on many of the
spoils to establish quick cover. Subsequently, one-half of each plot was fertilized with
nitrogen and phosphorus, and one-half was left unfertilized as a check on the value of
fertilization.
Greenhouse trials: To complement the field studies, several of the more promising species were also evaluated in greenhouse studies. Spoils ranging in pH from about
3.5 to 6.0 were collected and used to determine relative tolerances of the test species to
acid spoil. Each collection of spoil was screened through a 1/2-inch sieve and thoroughly
mixed before it was put into pots. To minimize growth differences due to inherent variation in fertility among spoils, all pots were fertilized with nitrogen at 50 ppm of spoil and
phosphorus at 21 ppm. Herbage yields were compared after forty to sixty days of
growth.
All greenhouse tests of grasses included weeping lovegrass as a standard for
comparison. The lovegrass seed used in all field and greenhouse tests was obtained from
a commercial source.
Herbaceous Mixtures
Weeping lovegrass was included in several mixtures of grasses and legumes
evaluated for providing quick yet persistent cover on a variety of strip-mine spoils. Of
special interest was the compatibility of weeping lovegrass with slower-developing
grasses and legumes.
154
Competition with Direct-Seeded Black Locust
Black locust (Robinia pseudoacacia) is the tree species most often planted on
steep outslopes of spoil banks in Appalachia. In the past, most black locust was established with hand-planted seedlings, but direct seeding this species on steep outslopes is
easier, safer, and less costly than hand planting. In addition to establishing trees, a
quickly established cover of herbaceous vegetation is also needed. So we studied the
influence of several herbaceous species on the establishment and growth of black locust
seeded with the herbaceous vegetation.
Plots were established in which black locust was sown alone and with different
grasses and legumes or mixtures of grass and legumes. The pH of the spoils ranged from
about 5.5 to 7.6. Black locust was sown at a rate of 3 pounds per acre, and the plots were
fertilized with N at 60 pounds per acre and P at 44 pounds per acre. In the fall, the
number and height of black locust seedlings were determined, and percent ground cover
was estimated in each plot.
Results
Species Adaptation Trials
Field plots: When analyzed over all the plots for all the years, fertilized weeping
lovegrass provided more ground cover in the first growing season than any other species
tested (Table 1). This was especially important on extremely acid spoils (pH 4.0-4.5)
where weeping lovegrass often made a satisfactory ground cover (60 to 90 percent) in
one growing season, whereas most other species made little or no cover. With favorable
spoil and a cool, wet summer, some fast-growing, cool-season grasses like annual and
perennial ryegrasses (Lolium spp.) sometimes provided effective cover faster than weeping lovegrass. But in relatively dry years, weeping lovegrass was better adapted to the
droughty environment that occurred on spoil banks during late spring and summer.
Weeping lovegrass stands usually died out after two or three years in our plots.
On north-facing slopes, the plants often died after one year, but on level benches and
south-facing slopes, they sometimes lived as long as four years. This short-lived effect is
consistent with reports from other areas including Georgia (Richardson and Diseker,
1965), West Virginia (Tyner, Smith and Galpin, 1948), Arizona (Pond, 1968), Mississippi
(McClurkin, 1967), South Africa (Cresswell, unpublished), and Japan (Usui and Suzuki,
1969).
Weeping lovegrass will spread onto adjacent barren spoils by natural seeding from
established plants, but it is not an aggressive spreader and poses no threat as a potential
weed in cultivated land.
155
Table 1. Percent Ground Cover Established in One Growing Season
Species
Cover
NF (%)1 F (%)2
Plots
Averaged
NF (#) F (#)
Years
Averaged
NF (Yrs.) F (Yrs.)
Pct.
Pct.
No.
No.
Yrs.
Yrs.
Grasses
Weeping lovegrass
Bermudagrass
Orchardgrass ‘Potomac’
Ryegrass, perennial
Redtop
Ky-31 tall fescue
Switchgrass ‘Blackwell’
15
15
10
10
5
5
5
80
65
55
55
55
35
20
37
22
11
13
13
29
29
34
15
14
16
11
27
24
6
4
2
3
3
6
6
5
3
2
3
2
5
5
Legumes
Kobe lespedeza
Korean lespedeza
Birdsfoot trefoil ‘Viking’
Sericea lespedeza
Crown vetch ‘Chemung’
20
15
20
10
5
50
40
40
20
15
17
20
22
27
24
10
11
24
22
23
3
4
5
6
4
2
3
4
5
3
1
NF = Not fertilized.
F = Fertilized with N and P.
2
As is evident from Table 1, fertilizer is essential for the establishment of quick
cover. Nitrogen fertilizer is nearly always needed, especially for the grasses. Many
spoils also require additions of phosphorus for satisfactory grass and legume growth.
Potash fertilizer was not needed for the establishment of ground cover in any of our
studies.
Greenhouse trials: First results of the greenhouse studies substantiated our field
results in that weeping lovegrass is the most acid-tolerant herbaceous species that we
have tested. It yielded nearly as much in spoils with pH of 4.0 as in spoils with higher
pH (Table 2). Yields of most of the other grasses, except Blackwell switchgrass (Panicum virgatum), declined in spoils with pH below 4.5. The reduced yields of orchardgrass
(Dactylis glomerata) and Ky-31 tall fescue (Festuca arundinacea) in soil appeared to be
caused by soil pathogens.
In a second trial, the growth of several accessions of Boer lovegrass (Eragrostis
chloromelas), Lehmann lovegrass (E. lehmanniana), King Ranch bluestem (Bothriochloa
ischaemum), and Caucasian bluestem (B. caucasica) was compared with weeping
lovegrass in soil and several acid spoils. Boer lovegrass performed about the same as
156
weeping lovegrass, but Lehmann lovegrass and the bluestems produced poorly or not at
all in the three spoils (Table 3).
Table 2. First Trial: Herbage Yields of Grasses Grown in the Greenhouse in Soil and
Mine Spoils (Grams/Pot, Oven-Dry)
Species
Weeping lovegrass
Blackwell switchgrass
Redtop
Orchardgrass
Ky-31 tall fescue
1
Soil
pH 6.7
9.9
5.9
4.5
2.9
2.5
5.6
7.6
5.5
3.8
3.9
3.6
4.9
7.5
5.2
3.2
3.5
3.3
4.5
7.9
4.3
3.3
3.0
2.7
Spoil pH
4.3
4.0
8.7
8.1
4.9
1.6
2.7
.4
1.9
.1
.5
.1
3.8
5.4
1.5
.4
.1
.1
3.7
1.0
.1
(T)1
(T)
(T)
T = Trace or < .05 g.
Table 3. Second Trial: Herbage Yields of Grasses Grown in the Greenhouse in Soil and
Mine Spoils (Grams/Pot, Oven-Dry)
Soil
pH 6.7
4.0
3.2
2.8
2.3
3.0
Species
Weeping lovegrass
Boer lovegrass
Lehmann lovegrass
King Ranch bluestem
Caucasian bluestem
1
4.6
3.2
2.8
1.3
(T)
.3
Spoil pH
4.2
2.9
2.4
1.1
(T)
(T)
3.9
2.0
1.8
(T)1
.0
(T)
T = Trace or < .05 g.
Herbaceous Mixtures
In general, weeping lovegrass is a good companion species with long-lived
grasses and legumes. It usually provided the desired quick cover, yet did not choke out
the slower-developing companion species.
When sown with weeping lovegrass, cool-season species like tall fescue, birdsfoot
trefoil (Lotus corniculatus), and crown vetch (Coronilla varia) usually have a chance to
germinate and become established to some degree in the spring before the lovegrass
makes its major growth. In the fall, when lovegrass stops growing and goes dormant, the
established cool-season plants make additional growth. The following spring, these wellestablished cool-season plants start growing before lovegrass and soon replace it.
157
Sericea lespedeza (Lespedeza cuneata), a commonly used warm-season legume,
can also be established with weeping lovegrass, although sometimes more slowly than
the cool-season legumes. The rapidity with which companion grasses or legumes replace
lovegrass appears to be influenced by the interrelations of yearly weather conditions,
spoil texture and moisture, spoil acidity and natural fertility, surface temperature, and
aspect.
One advantage of using lovegrass with other grasses and legumes on spoils of
various acidity levels is that a greater percentage of spoil area may be vegetated because
lovegrass will survive in spoils too acid for the other species. Another advantage is that,
in a year with a relatively dry spring, the cool-season species often make very little
growth, but lovegrass will still produce cover during late spring and summer. For example, in one year with a dry spring, mixtures that included weeping lovegrass provided
about twice as much cover as those without lovegrass. The following year was cool and
wet during the spring and most of the summer. Most of the mixtures seeded that spring
with lovegrass provided little additional cover compared to those without lovegrass.
Annual and perennial ryegrasses compete strongly with lovegrass and most other
species. In a favorable spring, ryegrass may provide cover much sooner than lovegrass,
but the ryegrass often chokes out companion species. Some plots with good cover of
annual ryegrass the first year had very little cover either from volunteer ryegrass or the
companion species the second and third years. In our plots, perennial ryegrass lived two
to three years, about as long as weeping lovegrass.
Competition with Direct-Seeded Black Locust
Seeded herbaceous vegetation, when fertilized, will compete with direct-seeded
black locust. However, the degree of competition varies with different herbaceous
species. Weeping lovegrass is one of the least competitive species we have used, even
though it provided more ground cover than the other species tested (Table 4). The average number of twenty-four black locust seedlings per plot with weeping lovegrass represented better than adequate stocking (twenty tree seedlings per plot was considered
adequate stocking). Average seedling height was about 3 inches less than that of the
seedlings in the control plots.
It is apparent that the cool-season grasses, especially the ryegrasses, were the
most competitive with the locust seedlings. Birdsfoot trefoil, a cool-season legume, was
not so competitive, probably because it did not make much cover until the fall.
Similar field studies were conducted in the two preceding years, using herbaceous
mixtures. The results were similar in that mixtures dominated by weeping lovegrass were
less competitive with black locust seedlings than mixtures dominated by fescue and
ryegrass.
158
Table 4. Percent Herbaceous Cover and Number and Height of Black Locust Seedlings
in Herbaceous Species Plots (Average of Four Replications)
Species
Natural vegetation2
Weeping lovegrass
Kobe and Korean lespedeza
Birdsfoot trefoil
Sericea lespedeza
Ky-31 tall fescue
Perennial ryegrass
Annual ryegrass
Herbaceous
Cover (%)1
15
80
45
40
25
60
70
70
Black Locust Seedlings
Number
Height
on .02 Acre
(Inches)
54
10
24
7
22
7
18
7
31
6
15
5
9
4
9
3
1
Evaluated at the end of the first growing season.
None seeded.
2
Discussion
The use of weeping lovegrass for providing cover on eroded and disturbed land is
nothing new. This grass has been used for many years for stabilizing roadsides and
eroded and abandoned lands in the southwestern and southeastern United States
(Denman, Elder, and Heller, 1953; Richardson and Diseker, 1965; McClurkin, 1967). It
is a consistently successful species for vegetating sand and slime dumps in South Africa
(F. H. Lancaster, unpublished) and in Japan for revegetating land that has been denuded
by gases from smelting copper and subsequent erosion (Usui and Suzuki, 1969). Similarly, its tolerance to extremely acid soil and subsoil was demonstrated by Cummings
(1947) in the Copper Basin of Tennessee. But only recently, as a result of U.S.D.A.
Forest Service revegetation studies in Kentucky and West Virginia, has this grass been
tried intensively and extensively on coal-mine spoils in Appalachia.
Reducing erosion and sedimentation is the primary reason for establishing grasses
and legumes on most of the spoils in Appalachia. The sooner the cover can be established, after the mining disturbance is over, the better. Some spoils are extremely acid,
but fortunately these are in the minority. However, using the most acid-tolerant plants
available permits just that much more of the spoil areas to be covered. Weeping
lovegrass is beneficial for providing quick cover on a wide range of spoil conditions,
including many of the more acid ones. This grass is tolerant of many spoils with pH as
low as 4.0, and will grow in a few spoils with a slightly lower pH.
Even on the less acid spoils, including lovegrass in herbaceous seed mixtures is a
good practice for if the cool-season species fail to produce cover because of a dry
159
spring, weeping lovegrass usually will still produce cover during the late spring and
summer.
Weeping lovegrass is relatively short-lived on spoils in Appalachia. Under most
conditions, this is no serious drawback because lovegrass is not strongly competitive with
companion species. Therefore, it can be used in mixtures with long-lived species that
will replace the lovegrass and become dominant in two to three years. This appears to be
consistent with the role of weeping lovegrass as a subclimax species on abused lands in
its native Africa (Denman et al., 1953).
Further, weeping lovegrass is not strongly competitive with seeded black locust,
or assumedly with planted trees. So even if pure stands of lovegrass die out in two or
three years, it will have provided ground cover until the trees themselves start producing
some site protection. In a good stand of lovegrass, the heavy litter alone will provide an
additional year of ground cover.
To maintain stands on mine wastes in South Africa, weeping lovegrass is burned
during the dormant season (C. Cresswell, unpublished). Grazing or burning is suggested
as a practice on Arizona rangeland to reduce deterioration of weeping lovegrass stands
(Pond, 1968). We have not experimented with burning or foliage removal treatments for
maintaining weeping lovegrass stands on spoil banks. Although burning or mowing may
possibly extend the life of weeping lovegrass stands, these practices probably will have
little use on spoil banks in Appalachia because they would damage or destroy trees
normally planted with the lovegrass.
On spoils with pH 4.5 or above, other species could sometimes be used for quick
cover. This could include cool-season species like ryegrass, cereal rye, oats, and wheat,
or summer annuals like Sudangrass and pearl millet. Ryegrass and, to some degree, the
cereals have the disadvantage of being strongly competitive with companion grasses and
legumes and with tree seedlings. To establish similar ground cover, the cereal grains and
summer annuals would require much greater volumes of seed as compared with a couple
of pounds of weeping lovegrass seed. When seeding by aircraft, using the smallest
possible volume and weight of seed is most advantageous.
Furthermore, spoil banks are normally seeded by broadcasting seed on unprepared
seedbeds. It seems feasible that seed size may have some influence on success of establishment of different species. Tiny seeds of weeping lovegrass have a better chance of
being covered in small crevices or under spoil particles than do larger seeds, which are
more likely to remain uncovered on the surface.
Summary and Conclusion
In the humid east, spoil banks formed by strip-mining for coal need to be revegetated as quickly as possible after mining is completed to protect soil and water value of
watersheds, improve aesthetics, and return the disturbed land to some productive use.
160
Weeping lovegrass has provided initial cover on extremely acid strip-mine spoils faster
than any other herbaceous species tested. It has grown well in spoils with a pH as low as
4.0, whereas most other grasses do poorly below pH of 4.5. It is also better adapted to
drier sites and summer growing conditions than are the more commonly used cool-season
grasses. To establish rapid cover with weeping lovegrass, or any grass, nearly all spoils
need to be fertilized with nitrogen, and many spoils also need phosphorus.
Weeping lovegrass is relatively short-lived in the Appalachian region, but it works
well in mixtures with other slower-developing permanent grasses and legumes. It provides the desired quick cover during the first growing season, but does not crowd out the
companion species, which usually obtain dominance the second or third growing season.
For establishing tree cover, black locust is often seeded with herbaceous species,
especially on steep outslopes of spoil banks. Weeping lovegrass provides good ground
cover, yet is less competitive with the locust seedlings than are other oft-used cool-season
grasses such as ryegrass and tall fescue.
Although not a panacea or cure-all for reclaiming strip-mined land, weeping
lovegrass plays a valuable role in providing quick cover on barren acid spoils and
complements other revegetation practices.
Literature Cited
Cummings, W. H. 1947. Weeping lovegrass, Eragrostis curvula, seeding test results in
the Copper Basin. Agron. J. 39:522-529.
Denman, C. E., W. C. Elder and V. G. Heller. 1953. Performance of weeping lovegrass
under different management practices. Okla. Agr. Exp. Sta. Tech. Bull. T-48. 18 p.
McClurkin, D. C. 1967. Effects of selected grasses and legumes on soil erosion and soil
recovery rates. USDA Forest Serv. So. Forest Exp. Sta. 1 p.
Pond, Floyd W. 1968. Changes in grass production on ungrazed converted chaparral.
USDA Forest Serv. Rocky Mt. Forest & Range Exp. Sta. Res. Note RM-98. 4 p.
Richardson, E. C. and E. G. Diseker. 1965. Establishing and maintaining roadside cover
in the Piedmont Plateau of Georgia. Agron. J. 57:561-564.
Tyner, E. H., R. M. Smith, and S. L. Galpin. 1948. Reclamation of strip-mined areas in
West Virginia. Agron. J. 40:313-323.
Usui, H. and H. Suzuki. 1969. Ecological and revegetational problems in Ashio devastated area. In press. Pa. State Univ. Internat. Symp. on Ecology and Revegetation
of Drastically Disturbed Areas.
161
Weeping Lovegrass Evaluations1
Arnold G. Davis2
Jacob C. Garrison3
Weeping lovegrass, Eragrostis curvula (Schrad.) Nees, is widely used as a pasture
grass throughout many parts of north, east, and central Texas. It is highly regarded as a
forage plant for winter grazing as it usually contains a high percentage of green leaves
during the dormant winter season.
Many grazing systems containing weeping lovegrass and coastal bermudagrass in
separate pastures are being used successfully. Weeping lovegrass provides dormant
season grazing and starts growth earlier in the spring than bermudagrass. Coastal
bermudagrass provides the major portion of the grazing during the warm growing season.
Limited plantings of weeping lovegrass have been made with other grasses for range use.
‘Ermelo’ weeping lovegrass and the first released strain of weeping lovegrass,
called common in the commercial trade, have been extensively used. Both strains are
classified as Eragrostis curvula.
Since Eragrostis curvula is an apomictic species (Streetman, 1963), it is to be
expected that there will be a large number of strains (Leigh, 1967). From this, we could
assume that potential for selection of improved strains is feasible.
The main criterion for selection of a pasture grass is herbage yield. The yield of
crude protein is a better indication of the value of the herbage, but such figures should be
interpreted with care in the absence of digestibility trials (Leigh, 1967).
The Soil Conservation Service has evaluated several introduced accessions of
weeping lovegrass at the James E. “Bud” Smith Plant Materials Center, Knox City, Texas.
Preliminary selections were made at this location for further evaluation under field
conditions on the farms and ranches of conservation district cooperators. Field plantings
are made to directly compare the new selections to common weeping lovegrass and
Ermelo weeping lovegrass. The final proof for accepting or rejecting a new strain is
obtained from these field plantings in a grazing situation. Other state and federal agencies assist in obtaining information about cattle preference and performance.
Methods and Materials
Fifteen introduced strains of weeping lovegrass were assembled at the SCS James
E. “Bud” Smith Plant Materials Center in early 1965. They were planted May 12, 1965,
2. Plant Materials Specialist, Soil Conservation Service, P. O. Box 648, Temple, Texas 76501.
3. Manager, Plant Materials Center, Soil Conservation Service, P. O. Box 27, Knox City, Texas 79529.
162
in 20-foot rows spaced 40 inches apart. Seeding was accomplished with a hand planter.
Seeding rates were not calculated, but a dense uniform stand of each accession was
obtained.
The soil is a Miles fine sandy loam that had been farmed in cotton and milo for
many years prior to 1965. The pH is 8.0; it is low in nitrogen, moderate in available
P2O5, and high in potash.
All residue was removed to a height of 6 inches during early February of each
year. This allowed each accession equal opportunity to initiate growth in the early spring.
All plantings were irrigated and kept weed free. No fertilizer was applied in
1965. Observations and forage yields were recorded during the period 1965–67.
Forty pounds of nitrogen and 40 pounds of phosphate were broadcast in the early
spring of 1967. The fertilizer was incorporated into the beds with a rolling cultivator.
Notes were kept on seed production, forage production, leaf production, winter
injury, rapidity of spring recovery, percentage green leaves retained in winter, drought
stress, and recovery following clipping. No facilities are available for grazing tests at the
Center; this must be done at other locations.
All accessions were clipped at 4 inches during 1966 and 1967, and the average
forage yield is shown as a percent greater than, or less than, Ermelo and common.
In addition, 1 acre each of PI-208994 (PMT-603) and PI-232813 (PMT-604) was
established for seed increase at the request of the Agricultural Research Service in Oklahoma. The PI numbers were assigned by New Crops Research Branch, Crops Research
Division, Agricultural Research Service. PMT numbers are assigned each accession
grown at Knox City, Texas. Seed was harvested from each of these fields and allocated
to the conservation agronomists, SCS, Texas, and Oklahoma, for placement through the
local soil and water conservation districts. These accessions were planted in “cafeteria
style” plantings, with Ermelo weeping lovegrass and common weeping lovegrass as
standards throughout most of Texas. Twenty-two field plantings of PMT-603 and PMT604 were made in Texas during 1966–1969.
Initial Observation—Studies—James E. “Bud” Smith Plant Materials Center
(Fifteen Accessions)
The following table is a summary of the performance of fifteen accessions of
weeping lovegrass during the period 1965–1967:
163
PMT
Other
Number Number
722
603
604
718
719
720
721
723
724
725
726
727
728
729
730
1138
Ermelo
PI-208994
PI-232813
PI-295689
Common
PI-295690
PI-295691
PI-295693
PI-295694
PI-295697
PI-295700
PI-295703
PI-295707
PI-299914
Seed
Prod.1
G
F
F
G
G
G
G
G
F
G
F
G
G
G
F
G
Average Early
Forage Winter
Prod.2 Green3
1.00
.81
.90
.92
1.00
.85
.87
.88
.95
1.21
.82
.*
.88
1.25
1.02
.49
50
50
60
90
80
50
70
50
40
90
90
90
90
90
40
50
Winter
Spring
Drought
4
5
6
Injury Recovery Leafiness Stress7
1
1
1
1
1
3
1
1
1
5
5
7
3
5
1
1
10”
8
9
11
8
9
10
12
10
9
8
4
16
10
10
9
MA
SP
MA
MA
MA
A
MA
MA
MA
SP
SP
SP
SP
SP
MA
SP
S1
S1
S1
S1
S1
S1
VS1
M
M
M
S1
VS1
S1
S1
S1
M
*Sparse regrowth did not justify measuring forage yield.
1
Seed Production: G = Good, F = Fair.
2
Average Forage Production: Forage yield, expressed as a percentage, greater than or less
than standards.
3
Evaluated visually following several hard freezes in December, 1965. Expressed as
approximate percentage green leaves.
4
1 = 0–20 percent, 3 = 20–40 percent, 5 = 40–60 percent, 7 = 60–80 percent.
5
Vegetative growth, measured as inches of new growth on March 22, 1967.
6
A = Abundant, MA = Moderately Abundant, SP = Sparse.
7
VS1 = Very Slight, S1 = Slight, M = Moderate.
164
Little difference in forage production was expressed between the fifteen strains
evaluated, with the exception of PMT-1138. The lower production of this accession can
be attributed to the poor stand and the fact that it was planted later than the other accessions. Only two accessions produced more forage than Ermelo and common weeping
lovegrass, two were essentially the same, and ten produced slightly less forage.
Seed production varied slightly, but it should be remembered that the cultural
practices applied to this study were not directed primarily toward seed production.
Early winter greenness, amount of green leaves present following several hard
freezes, is an indication of the potential forage value of the plant during the early winter.
Observations indicated that some plants were severely damaged later in the winter, and it
might be possible to produce these strains for south Texas use exclusively. Another factor
not shown here is the capability of the plant to produce a flush of green growth during a
warm period in the winter. This varies considerably between accessions grown at other
locations as well as at Knox City.
Weeping lovegrass generally has a good capacity to endure drought periods.
Summer dormancy is developed during severe stress situations, but full recovery was
adequate for all strains evaluated.
Winter injury varies considerably. Some strains have much less ability to endure
cold; PMT-727 is an example of this type. Spring recovery at Knox City is closely
associated with winter injury. Early abundant growth is important, but this factor is
difficult to anticipate between locations and is in part dependent upon the year and
cultural practices employed. Seedling vigor and early plant development were about the
same for all strains evaluated.
PMT-718 and PMT-729 were selected for further evaluation. PMT-718 starts
growth earlier in the spring than the other accessions studied. It retains a large number of
wide green leaves during the winter months. PMT-729 is a robust blue form (Leigh,
1967) of limited winter hardiness that has possibility for use in central and south Texas.
PMT-603 and PMT-604—Seed Production—Knox City
Seed production of PMT-603 and PMT-604 at the James E. “Bud” Smith Plant
Materials Center was as follows:
Selection
1965
1966
Pounds per Acre
1967
1968
1969
Average
PMT-603
Pmt – 604
54
56
106
107
170
180
383
314
209
197
335
330
The largest portion of the seed produced each year was made in June. Only a
token amount of seed was obtained from October harvests in 1967 and 1968. These fields
were fertilized in the summer each year following a dormant period and then irrigated for
165
a fall seed crop. The most seed obtained in a fall harvest by using these methods was 40
pounds per acre in 1966.
Forty-five pounds of nitrogen per acre was applied in the early spring and again in
late July each year. Phosphorus, 45 pounds per acre, was applied in 1966.
PMT-603 and PMT-604—Field Studies
Seven hundred and twenty pounds of seed of PMT-603 and a like amount of
PMT-604 were distributed during the period 1966–1969. Twenty-two plantings comparing these to Ermelo and common weeping lovegrass were made as follows:
Year
1966
1967
Number of Plantings
2
4
1968
8
1969
8
Locations—Texas
Baird, Rising Star
Wheeler, Tyler,
Nacogdoches
Vernon, Midland, Tyler,
Sulphur Springs, Rosebud,
Gonzales, Bowie, Bonham
Morton, Anson, Linden,
Caldwell, Pleasanton,
Lockhart, Seguin
All four strains of weeping lovegrass were planted separately within one pasture
to evaluate differences in palatability. Livestock had free choice to all four strains.
Cages were used to determine ungrazed forage production in some of the plantings, and
visual observations of livestock grazing habits were made.
In no case was any one strain fenced out separately and livestock performance
determined by weight measurement. Consequently, no difference in inherent effectiveness of one strain to produce better gains was recorded. This is unfortunate, because it is
now commonly recognized that the true criteria for determining the advantage of one
strain over another should be related to better animal performance or increased animal
gain.
Seventeen of the twenty-two plantings were established successfully. Stands were
not obtained in five plantings, because of drought or other reasons. Eleven of these
plantings had been grazed by the end of 1969; one planting was cut for hay. All were
grazed by cattle, except for one planting that was grazed by horses.
Fertilizer was applied to thirteen of the seventeen plantings. The amounts applied
per year ranged from 16 to 75 pounds of nitrogen and 20 to 30 pounds of available
phosphorus. Fertilizer application increased the palatability of all strains. This was
particularly evident on one planting where uneven distribution created grazing problems
166
when the cattle overgrazed the fertilized strips and rejected the grass growing in the
unfertilized areas.
A consistent pattern of livestock preference for one of the four strains could not
positively be established, but palatability differences might become more evident as the
plantings reach maturity. Common weeping lovegrass was reported as being less vigorous, less effective, or slower to develop in the seedling stage in three plantings. In no
case was it reported that common was substantially less productive or not readily eaten
by livestock.
Summary and Conclusion
Fifteen strains of weeping lovegrass were studied at the SCS James E. “Bud”
Smith Plant Materials Center during the period 1965–1967. Considerable differences
exist between strains in winter hardiness, spring recovery, and numbers of green leaves
present during the winter months. Two strains, PMT-718 and PMT-729, were selected for
further evaluation as a result of these studies. Limited plantings of these strains will be
made at selected locations to determine animal performance. Ermelo weeping lovegrass
and common commercial weeping lovegrass will be used as the standards for comparison.
Seed of PMT-603 and PMT-604 was harvested from a 1-acre field of each at the
Plan Center, Knox City, Texas, during 1965–1969. Seed yields averaged approximately
200 pounds per acre per year, with the main part of the total production occurring in the
late spring. Management practices in these fields have failed to produce a second seed
harvest that justifies the costs involved.
Seventeen successful plantings of PMT-603 and PMT-604 were made on farms
and ranches of soil and water conservation district cooperators during 1966–1969. The
sole objective of these plantings was to compare these strains directly to Ermelo and
common weeping lovegrass for palatability differences. Field studies indicated no
consistent differences in acceptability by cattle or in production of the four strains involved.
References
Leigh, J. H. 1967. Comparisons between strains of Eragrostis curvula in South Africa.
Expl. Agric. 1967. 3. Pp. 327-335.
Streetman, L. J. Wrightia, A. Botanical journal. Vol. 3. March 1963. Number 3. Published by Texas Research Foundation, Renner, Texas.
167

Proceedings: Weeping Lovegrass Symposium

Transcription

Similar documents

Select Florida Native Grasses for North Central Florida

Dairymaster

Tintern Girl`s Grammar School

Weeping Blue Atlas Cedar

Durana White Clover

Evaluation of Warm-Season Perennial Grasses

Weeping Yaupon Holly

Weeping Yaupon Holly

Hammons - Cassgram

Hammons - Cassgram