Cupressus arizonica
Cupressus arizonica, the Arizona cypress, is a North American species of tree in the cypress family Cupressaceae, native to the southwestern United States and Mexico. Populations may be scattered rather than in large, dense stands. Description. "Cupressus arizonica" is a coniferous evergreen tree with a conic to ovoid-conic crown. It grows to heights of , and its trunk diameter reaches . The foliage grows in dense sprays, varying from dull gray-green to bright glaucous blue-green. The leaves are scale-like, 2–5 mm long, and produced on rounded (not flattened) shoots. The seed cones are globose to oblong , 15–33 mm long, with 6 or 8 (rarely 4 or 10) scales, green at first, maturing gray or gray-brown about 20–24 months after pollination. The cones remain closed for many years, only opening after the bearing branch is killed (in a wildfire or otherwise), allowing the seeds to colonize the bare ground exposed by the fire. The male cones are 3–5 mm long, and release pollen in February–March. Taxonomy. Up to five varieties are distinguished by some botanists, and these are sometimes treated as distinct species: Distribution. "Cupressus arizonica" is found mainly in the southwestern United States (Arizona , Utah, southwestern New Mexico, and southern California, with a few populations in southern Nevada and in the Chisos Mountains of western Texas), and in Mexico (Coahuila, Nuevo León, Chihuahua, Sonora, Durango, Tamaulipas, Zacatecas and northern Baja California). In the wild, the species is often found in small, scattered populations, not necessarily in large forests. An example occurrence is within the Sierra Juárez and San Pedro Mártir pine–oak forests of Mexico, where it is found along with canyon live oak and California fan palm. Uses. Arizona cypress, particularly the strongly glaucous "C. arizonica" var. "glabra", is widely cultivated as an  ornamental tree. Unlike Monterey cypress, it has proved highly resistant to cypress canker, caused by the fungus "Seiridium cardinale", and growth is reliable where this disease is prevalent. The cultivar 'Pyramidalis' has gained the Royal Horticultural Society's Award of Garden Merit (confirmed 2017).