The trees listed in this fact sheet should help guide the homeowner in making informed plant selections. Not all of the trees listed in this publication will necessarily thrive throughout Oklahoma, nor have all been listed which could be grown in various locations within the state. Also, keep in mind that all trees have inherent problems with various susceptibilities to diseases, insects and environmental stresses. The best policy is to strive for tree diversity in the home landscape. Try a variety of trees, not only to guarantee survivability of at least most of the plantings but also to increase the diversity which often enhances the aesthetic quality of the landscape.
It should be noted that trees pictured are not necessarily the best or only appropriate trees for Oklahoma, nor have they been listed in order of desirability. However, they have been found to perform above average throughout many areas of the state, and they are commercially available from most Oklahoma nurseries and garden center outlets. Other trees listed below, but not pictured, may grow equally well in numerous given sites throughout the state.
Ten tips for new tree care
1. Dig the planting hole 2-3 times the diameter of the trees’s rootball.
2. Avoid digging the hole too deep since the tree should be planted at it’s original grade or slightly higher (1-2 inches above grade). If the tree is planted above grade it is important to cover the edges of the exposed rootball with soil tapered down to the surrounding soil line.
3. Fill in the planting hole with native soil and tamp lightly.
4. Do not overfertilize the new tree. A newly planted tree has a very limited capacity for utilizing fertilizer until it starts to establish itself.
5. Stake young trees (topheavy or planted in windy areas) when necessary but allow for sway. Remove all stakes after the first season if possible.
6. Avoid overpruning new trees. Leave lower limbs intact the first season if possible.
7. Keep a 5-6 feet weed- and turf-free circle around the tree. Place an organic mulch 1-3 inches deep around the tree.
8. Apply at least one inch of water weekly.
9. Wrap young trees as fall approaches. Tree wraps protect tender bark from rodent damage and environmental stresses as a result of temperature fluctuations. One should note that some young trees benefit from summer wrapping to avoid sunscald.
10. Winter irrigate, when temperatures remain above freezing for more than a few days, to avoid dehydration injury.
(Pistacia chinensis) is 25 to 35 feet at maturity. It has pest free foliage with attractive red or blue fruit on the females. It has an excellent orange-red fall color. Prune out the narrow forks when young. It is medium in growth rate and becomes rounded in habit at maturity and is hardy throughout Oklahoma (zone 6 to 9).
(Ulmus parvifolia) is 40 to 60 feet at maturity and has pest free glossy leaves. It may have good yellow fall color and has attractive red fruit. It has exceptional brownish-orange mottled bark. Prune out the narrow forks when young. With irrigation and fertilization, the growth rate will be fast. It becomes rounded at maturity. It is an excellent disease-free substitute for the American Elm and is hardy throughout Oklahoma (zone 4 to 9).
(Celtis occidentalis) is 40 to 70 feet at maturity. It is a very tough, ideal tree for difficult sites (drought). It has an occasional yellow fall color. It is susceptible to nipple gall, which will not harm the plant but may be unsightly. It has a medium to fast growth rate and is hardy throughout Oklahoma (zone 2 to 9). Pictured is a related species, C. laevigata (Sugarberry).
(Quercus shumardii) is 50 to 75 feet at maturity with shiny dark green foliage, and it is a pest free plant. It is not as susceptible to chlorosis (yellowing) as Pin Oak. It has a reddish-yellow fall color and medium in its growth rate. It is hardy throughout Oklahoma (zone 5 to 9).
(Taxodium distichum) is 50 to 80 feet at maturity with fern-like foliage. It is drought tolerant and is reddish-brown in fall color. It has attractive, rounded fruit. It becomes pyramidal at maturity and is medium to fast in growth rate. It may grow “root knees” in wet sites and is hardy throughout Oklahoma (zone 4 to 9).
Redbud [pictured is C. canadensis ‘Alba’ (Whitebud)]
(Cercis canadensis) is 20 to 30 feet at maturity. It is the state tree of Oklahoma and has durable green foliage and bright pinkish-purple flowers in spring. It has occasional yellow fall color. It has cinnamon-orange bark at maturity. The Redbud is particularly susceptible to herbicide injury (2,4-D). It can also be purchased with purple leaves; ask for ‘Forest Pansy’ redbud or look for double flowering types or those with white flowers (whitebud).
(Koelreuteria paniculata) is 30 to 40 feet at maturity and has attractive foliage with beautiful yellow flowers in summer and occasional yellow fall color. It has attractive “Chinese lantern-like” fruit and is an extremely adaptable tree. It becomes rounded in habit at maturity and is hardy throughout Oklahoma (zone 4 to 9).
(Ginkgo biloba) is 40 to 70 feet at maturity and has unique fan-shaped leaves. It has beautiful golden fall color and is extremely adaptable. It is pest free and is pyramidal to widespreading in habit at maturity. It is slow growing. Choose male selections to avoid foul smelling fruit. It is hardy east of Highway 81 (zone 3 to 9).
(Liquidambar styraciflua) is 50 to 75 feet at maturity with shiny star-shaped leaves and exceptional yellow-orange-red-purple fall color. It has messy fruit with prickly spines. It should be grown in the eastern half of the state and prefers moist soils. There are many improved varieties available and most become rounded in habit at maturity (zone 5 to 9).
(Betula nigra) is 40 to 70 feet at maturity and has attractive foliage with a showy, reddish-brown and white exfoliating trunk. It prefers moist soils and grows pyramidal to rounded in habit. It has a medium to fast growth rate. It grows in zone 4 to 9 (eastern Oklahoma native).
(Ilex decidua) is 10 to 25 feet at maturity with shiny green foliage (native, deciduous holly) and attractive red fruit that persists. It can be grown as a shrub or small tree, and there are many improved varieties available. It grows best east of Highway 81 (zone 4 to 9).
(Acer ginnala) is 15 to 20 feet at maturity with shiny three-lobed leaves. Some varieties have attractive red fruit. Ask for varieties with red fall color. It is quite adaptable and pest free and becomes rounded in habit at maturity. It too is hardy throughout Oklahoma (zone 3 to 8).
Michael A. Schnelle
Extension Ornamentals/Floriculture Specialist
Paul J. Mitchell
Dale M. Maronek
Former Professor and Head
Horticulture and Landscape Architecture Dept.