Propagation Pests and Diseases

Wax myrtle, Southern bayberry Myrica cerifera
Propagation
Wax myrtle may be propagated by seed or cutting. Seeds are collected in the autumn,
stratified at 40 F for 2-3 months and sown in the spring. Alternatively, the seed can be
sown in the fall and covered with ¼ inch mulch for natural stratification. Seed moisture is
essential. Germination should occur in 3-6 weeks.
Semi-hardwood stem tip cuttings taken in early summer and dipped in IBA Quick Dip
5000 ppm can be rooted under intermittent mist.
Problems with fungal diseases during rooting make propagation difficult.
Pests and Diseases
The current Insect Management Guide for Commercial Foliage and Woody Ornamentals
can be found at http://edis.ifas.ufl.edu/IG012. The current Professional Disease
Management Guide for Ornamental Plants can be found at http://edis.ifas.ufl.edu/PP123.
Eriophyid mites (bud mites)
Recognition: Leaf symptoms include leaf curling or folding, abnormal shape or
distortion, galls, discoloration or bronzing,
russeting, blisters and withering. These
problems are caused by a microscopic wormlike mite with only two pairs of legs. The
symptoms can be confused with symptoms of
viruses or herbicide damage. Symptoms
produced by eriophyid mites may persist for
several weeks after the mites have disappeared.
Contributing factors: unknown
Management recommendations: Most bud
mite damage can be tolerated on wax myrtle.
Eriophyid mites are host specific, so will not
spread to other plant species. For localized infestations, prune and dispose of
infested plant parts. Only a few specific miticides are effective against eriophyid
mites.
Fusaarium wiltt (Fusarium
m oxysporuum)
Recoognition: Loss of vigor, stunting, andd curled, willted and/or off-color
o
foliiage results
from Fuusarium wiltt. Individuall branches orr the whole
plant may
m die. A diistinctive broown-purple discoloration
d
n
of the xylem
x
can bee seen when looking at a cross
sectionn of the base of an infecteed stem.
Contributing factoors: The funngus is soil-bborne.
Nematoodes or root wounds mayy allow entryy of the
pathogeen. The probblem is concentrated in Central
C
and
South Florida.
F
Managgement recoommendatioons: Minimizze root
damagee during plannting and maaintenance. Inspect
I
all
plants beffore acceptinng them for installation.
i
There is no treatment foor infected
plants and
d they will eventually die. Remove infected treess and replannt with nonsusceptiblle species. Soil
S fumigation is necessary only if replanting
r
wiith wax
myrtle.
Inon
notus hearrtrot; Ptycchogaster wood
w
rot (Inonotus rickii
r
or
Ptychog
gaster cubeensis)
Reccognition: External
E
sym
mptoms very similar to
those caused byy Fusarium; i.e., loss of vigor
v
and
diebback. Additiionally, sap exudation
e
annd bark
staiining are diaagnostic. Cinnnamon brow
wn, beardlikee sporulatingg structures may
m be evideent near
wouunds or brannch stubs on the trunk. Branches
B
mayy
breaak easily. Innternally, thee decay will be
b spongy,
yelllow-brown or
o red-brownn, often fleckked with
whiite streaks (m
mycelium), and
a borderedd by a dark
purrplish zone of
o stained xylem.
Con
ntributing factors:
f
Thiss fungus spreads throughh
air--borne spores which enteer the plant through
t
wouunds in the wood.
w
It is asssociated moost often witth
mannicured, heaavily pruned wax myrtle but also
occcurs in naturaal stands.
Maanagement recommend
r
dations: Prevvention is
based on soundd maintenancce practices. Minimize
pruuning and othher causes off bark injuryy. Do not
pruune when spoorulating struuctures are noticed
n
in thee
areaa. Avoid plaanting infecteed plants; plants dug
from
m the wild may
m come froom infected stands and
shoould be inspeected carefullly. There is no treatmennt
for infected plaants except reemoval and replacement
r
t.
Sinnce the funguus is not soil borne, fumiigation is not
neccessary.
Botrryosphaeriia canker and
a dieback
Recognitiion: Externaal symptoms include cannkers, wiltingg
and diebacck of a brancch or branchhes of a tree or
o shrub.
Dark streaaks may be seen
s
in the wood
w
under the bark.
Cankers may
m be dark or sunken annd may be suurrounded byy
wound calllus. The funngi attack plaant tissue thrrough
wounds, growth
g
crackks, leaf scars and lenticells. Under
magnificaation, the small black funngal fruiting bodies may
be seen errupting throuugh the bark. The fruitingg bodies aree
white insidde when slicced open.
Contributing factorss: This disease organism
m attacks
stressed pllants and is spread
s
by prruning, air movement
m
annd
splashing water.
Managem
ment recomm
mendations: There are no
n effective
fungicide controls. Preevention is the
t best defense. Keep
o
culttural conditiions, avoid stress
s
and
plants in optimum
wounds, and
a maintainn sanitation.
Root knot nem
matodes
Reecognition: Nematodes
N
i
impair
the rooots, causingg
pooor growth, plant
p
declinee and thinninng of the
folliage. Infesteed roots mayy be brown and
a stunted
and have obvioous galls.
Coontributing factors: Higghest populaations of
nematodes occcur in well-ddrained sandyy soils wherre
preevious cropss have suppoorted populattions.
Management recommend
dations: Keep plants as
healthy as possible with addequate wateer and
ferrtilizer to suppport new rooots. No chemical
controls are avvailable for use
u on existinng plants.
When replacinng plants, rem
move all rooots and
repplace soil. Avoid
A
replantting with sussceptible
speecies, or fum
migate beforee replanting..
Sources
1. Elizabeth Bush. Botryosphaeria Canker and Dieback of Trees and Shrubs in the
Landscape. Virginia Cooperative Extension. http://pubs.ext.vt.edu/450/450-726/450726.html
2. Cathy Neal, Celeste White and Eleanor Foerste. Key Plant and Key Pests in Central
Florida Landscapes. University of Florida Extension slide set.
3. University of Florida Landscape Plant Propagation Information.
http://hort.ufl.edu/lppi/
Prepared by:
Juanita Popenoe, PhD, Commercial Horticulture
Lake County Extension, 1951 Woodlea Rd., Tavares, FL 32778-4052
Tel.: (352) 343-4101, FAX: (352) 343-2767
May 2010
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