TreeConnections - Tucson Botanical Gardens

Funding Provided By
Arizona State Forestry Division
TreeConnections
Benefit of Trees
Social benefits
Communal benefits
Environmental benefits
Economic benefits
Trees for Tucson gardens
Why plant trees???
Adds value to home property
More comfortable outdoor environment
Energy savings by shading the house
Privacy and more comfort inside
More attractive property
Increasing value as trees mature
Increased home value; about 15% with attractive landscaping
Guidelines for energy conservation
Learn the path of the sun throughout the year
Sunlight in the summer warms the east and west walls of homes
Sunlight in the winter warms the south walls
Use evergreen and deciduous trees correctly
Use evergreen trees to block cold winds northwest and north
side
Use deciduous trees to allow sun to warm the house in the winter
Use deciduous trees to shade the house during the hot months
Tree Selection and Care

Where to plant and not to plant trees

Appropriate trees for the garden size

How to plant

How to care for trees

Water issues
Where to plant trees
Place trees where they make outdoor
living more comfortable
For Privacy
For Screening unattractive views
Noise reduction
Proper placement for energy savings and
comfort
Where not to plant
• Never plant too close to structures or walls
• Do not plant trees too close to each other
• Avoid having “messy” trees overhanging patios
and driveways
• Do not plant to close to sidewalks
Acacia farnesiana – A.smallii - Sweet Acacia 15’ x 20’
Appropriate trees for your
garden
Large trees or small trees?
Evergreen or deciduous trees?
Canopy for shade or for privacy?
Fast growing or slow growing?
Large or Small Trees
First decide what type of tree you need
Trees that are too large for their site will need
extra pruning
Large trees are usually more work
Most important: Fit the tree to your property size
Parkinsonia floridum
Blue Palo Verde 35’ x 30’
Bauhinia lunaroides – Orchid tree 15’ x 12’
Evergreen or deciduous trees?
All trees loose their leaves, deciduous trees
leaves fall all at one time
Evergreen trees good for north-west and
north side of home
Deciduous trees good for east and south side
Evergreen trees good as permanent privacy
screen
Quercus - oak 50’ X 30’ or more
Lysiloma watsonii - Feather tree 15’ x 15’
Canopy shape of trees
Some trees have broad canopies, good for shade
trees:
Mesquites, Palo Verde, Vitex, Sweet Acacia
Tall, narrow canopies, good for privacy,
ornamental value, shading west side:
Acacia salicina, Desert willow, Oaks, Texas ebony
Prosopis velutina - Honey mesquite 10-20’ x 15-30’
Acacia salicina – Willow acacia 15-30’ x 15’
Fast or Slow Growing Trees
Palo Verde, Mesquite, Sweet Acacia, and
Desert Willow are some of the fastest growing
trees
Slow growing trees include Oaks, Ironwood,
Olive trees,
Acacia smallii - Sweet acacia 25’ x 15’
Olea europaea “Swan Hill” – Olive “Swan Hill”
How to plant trees in the desert Southwest
Staking young
trees
Caring for Trees
Fertilize
Use granular fertilizer, fertilize at the drip line
Plants in the Legume family - no need to fertilize
Pruning
Do not prune new plants for 2 years
Prune mature trees as needed
Never prune more than 20% off trees
Inspect trees annually
Bring in professional for major jobs
Check their work before hiring them
How to water
Water the root zone – 11/2 to 3 times as wide
as the canopy
Water 2 to 3 feet deep depending on the size
of the tree
Young plans watered more often than
mature plants
Water when the top 1/3 to 1/2 of the root
zone is dry
Plants with deep well developed roots need
water less frequently
Water Use in Plants
Important for everyone in Tucson and Arizona
Limited water available to all of us in the future
Water becoming more expensive
Many of our trees are drought tolerant
Native trees, as a rule, use less water
Always use a drip irrigation system, water saving
can be as much as 50%
Drought tolerance & Drought resistance
Most drought tolerant trees have special
adaptations to dry and hot climate such as small
leaves, leaves that have a thick and leathery
coating, grayish-green color and thick bark.
All plants need to have additional water for the
first two years after they are planted. Then
gradually cut back on the water. Only plants
that are classified as drought tolerant or drought
resistant can survive on natural rainfall.
Most trees will need additional water when we have
a prolonged drought.
Signs of over-watering
Soil is constantly damp
Leaves turn a lighter shade of green or turn yellow
Young shoots are wilted
Leaves are green yet brittle
Algae and mushrooms are growing
Signs of under-watering
Soil is dry
Older leaves turn yellow or brown, and drop off
Leaves are wilted
Leaves curl
Water Harvesting
Way to cut down on water bills:
Create berms and swales in the landscape
Capture the water that comes off the roof
Create “basins” around trees to capture water
Create terraces to slow down on drainage
Mulch all the plants with 3-4 inches of mulch
Water Harvesting
More plants die from over watering than under
watering.
Established trees will not need to be watered
more than once a month.
Water to a depth of 36” for established trees
Stress symptoms: Smaller leaves, green leaf
color “off”
Use a soaker hose at the drip line for extra
watering for stressed trees
Purchasing trees
Always check trees before purchase, check
for good pruning, no girdled roots, bark
without chips and nicks.
Check for good pruning. The leader of the
tree should not be pruned.
Avoid trees that are susceptible to Texas
Root Rot. Native trees are not susceptible.
(Cooperative Extension leaflet; Diseases of
Landscape trees)
Planting considerations
October is the best planting month
1. Don’t always buy the biggest size plant.
2. After digging a hole for the plant, fill it 1/3 with water - drain
3. Never dig a hole that is deeper than the height of the root ball.
4. Do not amend the soil.
5. Always remove the nursery stake.
6. Water every day for 10 days, then slow down.
7. Do not prune the plant for the first 2 years.
Trees for Tucson
Olneya tecota
Ironwood 15-30 x 20-25
Acacia schaffneri - Twisted acacia
15-20’ x 25’
Acacia schaffneri - Twisted acacia
Ebenopsis ebano – Texas ebony 15-25’ x x15’
Ebenopsis ebano
Texas Ebony
15’-25’ x 15’
Parkinsonia “Desert Museum” Palo verde “Desert Museum”
Size 20 x 30’
Parkinsonia microphylla – Foothill palo verde 10-20’ x 10-20’
Acacia berlandieri
Berlander acacia
15’ x 15’
Chilopsis linearis --Desert Willow 15 -18’ x 15’
Chiliopsis lineraris –
Desert Willow 15-18’ x 15’
Prosopis velutina – Honey mesquite 10-20’ x 15-30’
Cercis canadensis var. mexicana – Mexican redbud
12-20’ x12’
Cordia boissieri – Texas olive
10’-16 x 12’
Lagerstromia indica Crape myrtle 20’x 15’
Parkinsonia praecox - Palo Brea
15-30’ x 15-30’
Prosopis glandulosa --Texas Honey Mesquite
25’x 35’
Vitex agnus-castus – Chaste berry 20-25’ x 25’
Acacia aneura –
Mulga tree 12-20’ x 10-14’
Eysenhardia orthocarpa
Kidneywood 18’ x 15’
Pistacia lentiscus
Mastic tree
15-25’ x 15-20’
Pistacia chinensis - Chinese pistache 30’ x 50’
“Problem trees” in Tucson
Parkinsonia aculeta - Mexican palo verde
Tamarisk aphylla - Tamarisk
Rhus lancea - African sumac
Ailanthus altissima - Tree of Heaven
Melia azedarach - Chinaberry tree
All pine trees (Australian, Eldarica, Canary Island, Aleppo)
will grow to 40 – 50’
Funding Provided By
Arizona State Forestry Division
TreeConnections