   The Chinese Pistache Tree - April 14, 2004 Jeff Schalau, County Director, Agent, Agriculture & Natural Resources Arizona Cooperative Extension, Yavapai County What is the perfect tree for the home landscape? Most people want an attractive, low maintenance tree that grows fast, is pest and disease free, conserves water, and lives a long time. I’m sorry to say that no such tree exists. The problem: most fast growing trees are shorter-lived, use lots of water, and, if they survive, quickly outgrow the space available in the average residential landscape. Given this complex balancing act, the Chinese pistache (Pistacia chinensis) meets most of the above listed criteria and is an excellent tree for our area. The Chinese pistache is a medium to large deciduous hardwood tree that will fit into larger home landscapes. The leaves are compound pinnate (a long leaf stem with 11 to 17 leaflets) and alternately arranged. It has impressive fall color (scarlet, crimson, orange, sometimes yellow), even in milder climates. The tree’s canopy can reach 40-50 feet in height and 30 feet in width at maturity. It is virtually insect- and disease-free (although it is susceptible to Texas root rot). The Chinese pistache is dioecious: plants are either males producing pollen (with little or no allergenic qualities) or female producing attractive (but inedible) berries that attract birds. Once established, it is very drought, wind, and heat tolerant. The Chinese pistache is a close relative of the pistachio nut tree (Pistacia vera), but is much hardier. The wood is very hard and rot resistant. Young Chinese pistache trees should be planted in spring or fall. They must have full sun and do best in well-drained soil. However, they tolerate a wide range of soils, some alkalinity, and can live a very long time (several centuries). If there is a down side to the Chinese pistache, it’s that young trees appear spindly and awkward. Trees planted from five and fifteen gallon containers will probably need staking and grow slowly for the first three to five years after planting. Some structural pruning may also be necessary in the early years to develop an even canopy and proper branch spacing. Once they are established, they can grow two to three feet per year. All trees should be planted in a hole three to five times the width and only as deep as the root ball. Spring or fall planting is recommended. No amendments should be incorporated into the soil. The soil surface should be mulched to a depth of two to three inches and mulch should not touch the trunk. The soil should be allowed to dry on the surface between irrigations and never be soggy. Waterlogged soils are not suitable for Chinese pistache trees. As mentioned earlier, staking will probably be necessary on a newly planted Chinese pistache tree. The most common staking method uses two wooden stakes drive into the ground on opposite sides of the tree. Tie the tree to the stakes with soft tree ties (or panty hose). If using wire to tie the tree to the stakes, use soft rubber garden hose to protect the tree from damage from the wire. Allow the tree to have some movement as this will allow the trunk to become stronger. For more information on planting and staking, get the University of Arizona Cooperative Extension publication Planting Guidelines: Container Trees and Shrubs (available on-line at: ag.arizona.edu/pubs/garden/az1022.pdf). If you would like to see mature Chinese pistache trees, go to Cordes Junction and look around the freeway interchange where I-17 and Highway 69 intersect. There are a few Chinese pistache trees planted here along the road (I know it’s not the most convenient location). I hope that more people decide to plant these near-perfect landscape trees. The Chinese pistache is definitely an excellent choice for our area. The University of Arizona Cooperative Extension has publications and information on gardening and pest control. If you have other gardening questions, call the Master Gardener line in the Cottonwood office at 646-9113 ext. 14 or E-mail us at mgardener@verdeonline.com and be sure to include your address and phone number. Find past Backyard Gardener columns or submit column ideas at the Backyard Gardener web site: http://cals.arizona.edu/yavapai/anr/hort/byg/. |