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). Example of neoendemism and conservation challenges The ease of hybridization of cypress species in the American southwest has fostered a parallel history of taxonomic disagreements of where genus and species distinctions should apply. It thus provides a case study of neoendemism in conifers. Close taxonomic relatedness, in turn, offers both challenges and opportunities if and when assisted migration is considered as a mode of climate adaptation to prevent extinctions of endemic cypresses in the American southwest. References Further reading External links USDA Plants Profile for Hesperocyparis arizonica (Arizona cypress) as Hesperocyparis stephensonii as Hesperocyparis stephensonii Hike Arizona.com: Photos of Arizona Cypress (Cupressus arizonica) arizonica Flora of Arizona Flora of California Flora of New Mexico Trees of Coahuila Trees of Chihuahua (state) Trees of Sonora Trees of Durango Trees of Tamaulipas Trees of Zacatecas Trees of Baja California Flora of Texas Trees of the South-Central United States Trees of the Southwestern United States Flora of the Sierra Madre Occidental Flora of the Sierra Madre Oriental Natural history of the Transverse Ranges Plants described in 1882 Taxa named by Edward Lee Greene Least concern flora of North America