A tree to 20 m tall. Bark reddish when young, fibrous and stringy. Branches horizontal or slightly ascending, smooth red-brown to the sprays. Branchlets erect. Leaves acute, about 1.2 mm long with conspicuous glands and a strong ridge on the back, but rarely actively producing white resin dots, usually waxy to grey-green. Cones 1-2.5 cm wide, slightly waxy at first; scales 6-8 or sometimes 10, occasionally quite strongly pointed, often remaining closed for several seasons. Seeds smooth or warty, rarely with waxy bloom.
Recent revision recognises 6 natural varieties. A variable species that grows naturally in mountain habitats. Relatively rare in cultivation in Australia.
Montane Arizona, New Mexico, Mexico
With the possible exception of trees in Canberra, most plants offered under the name C. arizonica are best referred to the widely cultivated C. glabra, Smooth Arizona Cypress (sometimes recognised botanically as the variety C. arizonica var. glabra but maintained here as a species, these two species being widely confused). The Rough-barked Arizona Cypress is said to be easily distinguished from the Smooth Arizona Cypress by its stringy, finely and regularly fissured bark (often peeling in plates in upper branches), horizontal branches, greener foliage that does not exude white resin dots, and seeds that are not waxy blue. However, trees may be found in which these characters intergrade (possible hybrids). There is also a strong similarity between C. arizonica and C. lusitanica; these two species have natural distributions that overlap in the wild where they are known to hybridise and occasional trees are encountered in cultivation whose characters also intergrade suggesting hybridisation. Both species have bluish foliage with pointed leaves that have a strong ridge on the back producing 'square' tips to the branchlets. However, C. lusitanica can generally be distinguished by branchlets that are at least partly pendulous, leaves with inactive glands on the back, and young cones that are extremely waxy white. The cones of C. arizonica, which is rarely cultivated, are waxy grey only for a brief period, have pointed scales and are variable in size, being generally less than 1.75 cm in the first year but expanding with age.
ACT: Parkes (King George Terrace). VIC: Geelong (Eastern Park).
Source: (1995). Cupressaceae. In: . Horticultural Flora of South-eastern Australia. Volume 1, Ferns, conifers & their allies. The identification of garden and cultivated plants. University of New South Wales Press.
Narrowly conical, with blue-grey foliage. Hilliers Nursery, Winchester, UK, 1928. Tas: Hobart (Royal Tasmanian Bot. Gds).