This fast-growing, deciduous tree reaches thirty to forty-five feet and spreads twenty-five to forty-five feet or more, depending on conditions. It produces dark green, three- to six-inch-long leaves that are divided into multiple leaflets to form a dense, rounded canopy. The leaves turn a brilliant yellow in the fall just before falling off the tree. Its flowers are dioecious, with male and female blooms forming on separate trees. Male trees produce inconspicuous flowers in the spring that can cause a mess. Female trees drop a winged fruit that resembles a maple seed. It is drought resistant but grows best with occasional, deep irrigation during the hot, dry season. This tree is hardy to about ten degrees Fahrenheit. Plant it in full sun and well-draining soil. Careful pruning and branch selection ensures a strong trunk and stable branch development. Treat the tree with iron chelate fertilizer yearly or as needed to prevent iron chlorosis.
This plant is also susceptible to Texas root rot. The variety “Modesto” is symmetrical, compact and a little smaller in size but a vigorous grower. “Fantex” produces dark green, leathery foliage and is the best variety for residential landscapes. Use this magnificent tree for dense shade, as a street tree or in parks. It can also be used in large residential settings in combination with other evergreen plants. The Arizona ash is native to California, Texas, and Arizona. It is also endemic to Mexico, ranging from Northern Baja California east to Coahuila and Nuevo Leon, where it grows along canyons and water sources at 2,000 to 6,000 feet in elevation.