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Trees
The following are great shade trees for
Southern California school campuses. Suggested
by Frank McDonough, Horticulturist, and
Botanical Information Consultant, The Los
Angeles County Arboretum and Botanic Garden
Deciduous Shade
Trees
 London Plane Tree / Platanus
acerifolia
Mr. McDonough's first choice for schools.
"The best bet for lots of shade in the minimal
amount of time."
Can grow to 80 feet tall by over 40 feet wide.
A good choice where you want the maximum amount
of shade for your investment.
Does well in almost all Southern California
climates.
If irrigated properly, root damage is minimal
for a tree of its size.
Can be purchased in bulk quantities, bare-root,
from several So. California suppliers.
Additional information - UConn Plant
Database
 Maidenhair tree / Ginkgo biloba
Although slow growing at first, Ginkgo=s
hardiness in urban situations makes it
well worth the wait.
Besides growing to 80 feet in height and almost
60 feet in width, this tree puts on a
spectacular fall foliage show.
Plant only the male clones. (Female trees
produce a foul-smelling fruit).
Additional information - UConn Plant
Database
 Silk tree / Albizia julibrissin
Provides a broad, umbrella-like canopy of finely
cut leaves.
Its shade is somewhat less dense than other
shade trees, so it lends itself to shading
areas where more light might be required.
Produces beautiful pink pom-pom flowers in the
summer.
Be sure to get a variety resistant to Awilt@ (Verticillium).
 Oak trees / Quercus (sp.)
English oak/Q. rober; Red oak/Q. rubra; Pin
oak/Q. palustris
These deciduous oaks are spreading trees that
can grow over 65-80 feet tall.
Although water hungry and slow growing (about 2
- 3 feet per year) these oaks are
very long-lived and sturdy.
Additional information - UConn Plant
Database: (Search each individually.)
 Sawleaf Zelkova / Zelkova serrata
Vase shaped moderate sized shade tree.
Zelkova is a Japanese relative to the American
elm, but
less susceptible to diseases that make American
elms a poor choice.
Green Vase variety is fast-growing to 70 feet.
Additional information - UConn Plant Database
Mr. McDonough adds...
The above trees are all deciduous
species. There will be cleanup maintenance
in the fall when all the leaves are dropped, but
for most school-based applications this would
result in less overall maintenance compared with
the relatively constant messiness of evergreen
trees. Considering the size of the shade
canopy, there will be less problem with surface
root damage with the recommended deciduous trees
than with most evergreens. Of course,
there will be no significant shade provided when
a deciduous tree is bare, but when it leafs out
again in the spring, these trees do tend to
produce a better shade canopy.
Evergreen Shade Trees
In some situations, year-round greenery might be
preferred. For example, a few evergreen
trees might be sprinkled in among a
predominantly deciduous planting for a more
aesthetically pleasing landscape design.
Density of shade, growth rate, messiness, and
surface root damage were all taken into
consideration in the following three
recommendations by Mr. McDonough.
 Fern Pine / Podocarpus gracilior
Moderate growth rate to 30 feet.
Quite messy but excellent near foundations with
little risk of surface root damage.
Mr. McDonough's first choice evergreen shade
tree.
 Carrot Wood / Cupaniopsis anacardioides
A very beautiful evergreen tree.
Moderate to slow grower to 35 feet.
Subject to root rot with heavy water so not good
in lawns.
Produces fruit which can be messy.
Constantly sheds leaves.
 Australian Willow / Geijera parviflora
Not as dense a shade canopy as others above.
Slow to moderate growth.
Resents heavy watering (don't plant in lawn
area.)
Somewhat messy.
Additional Information:
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