Cupressus arizonica

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Cupressus arizonica
Cup glabra foliage.jpg
Cupressus arizonica var. glabra (smooth Arizona cypress) foliage
Scientific classification edit
Kingdom: Plantae
Clade: Tracheophytes
Clade: Gymnosperms
Division: Pinophyta
Class: Pinopsida
Order: Cupressales
Family: Cupressaceae
Genus: Cupressus
C. arizonica
Binomial name
Cupressus arizonica
Cupressus arizonica range map 1.png
Natural range of Cupressus arizonica. Does not show populations in central Arizona.
  • Callitropsis arizonica (Greene) D.P.Little
  • Hesperocyparis arizonica (Greene) Bartel
  • Hesperocyparis revealiana (Silba) Silba
  • Neocupressus arizonica (Greene) de Laub.
  • Callitropsis glabra (Sudw.) Carrière
  • Cupressus glabra Sudw.
  • Hesperocyparis glabra (Sudw.) Bartel
  • Callitropsis montana (Wiggins) D.P.Little
  • Cupressus montana Wiggins
  • Hesperocyparis montana (Wiggins) Bartel
  • Callitropsis nevadensis (Abrams) D.P.Little
  • Cupressus nevadensis Abrams
  • Hesperocyparis nevadensis (Abrams) Bartel
  • Callitropsis stephensonii (C.B.Wolf) D.P.Little
  • Cupressus stephensonii C.B.Wolf
  • Hesperocyparis stephensonii (C.B.Wolf) Bartel

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.


Cupressus arizonica is a coniferous evergreen tree with a conic to ovoid-conic crown. It grows to heights of 10–25 m (33–82 ft), and its trunk diameter reaches 55 cm (22 in). 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.[3]


Up to five varieties are distinguished by some botanists,[2] and these are sometimes treated as distinct species:


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).[4][3] 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,[5] where it is found along with canyon live oak and California fan palm.


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'[6] has gained the Royal Horticultural Society's Award of Garden Merit (confirmed 2017).[7]

Example of neoendemism and conservation challenges[edit]

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. [8] 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.[9]


  1. ^ Farjon, A. (2013). "Cupressus arizonica". IUCN Red List of Threatened Species. 2013: e.T42216A2962318. doi:10.2305/IUCN.UK.2013-1.RLTS.T42216A2962318.en. Retrieved 12 November 2021.
  2. ^ a b "Cupressus arizonica Greene". World Checklist of Selected Plant Families. Royal Botanic Gardens, Kew – via The Plant List. Note that this website has been superseded by World Flora Online
  3. ^ a b Eckenwalder, James E. (1993). "Cupressus arizonica". In Flora of North America Editorial Committee (ed.). Flora of North America North of Mexico (FNA). Vol. 2. New York and Oxford – via, Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
  4. ^ "Cupressus arizonica". SEINet, Southwestern Biodiversity, Arizona chapter. Photos, description, distribution map.
  5. ^ National Geographic 2001.
  6. ^ "RHS Plant Selector – Cupressus arizonica 'Blue Ice'". Retrieved 15 April 2020.
  7. ^ "AGM Plants – Ornamental" (PDF). Royal Horticultural Society. July 2017. p. 26. Retrieved 24 January 2018.
  8. ^ Rehfeldt, Gerald E (1997). "Quantitative analyses of the genetic structure of closely related conifers with disparate distributions and demographics: the Cupressus arizonica (Cupressaceae) complex". American Journal of Botany. 84 (2): 190–200.
  9. ^ Barlow, Connie. "Climate, Trees, and Legacy: 04 - Lessons of Arizona Cypress". youtube. ghostsofevolution. Retrieved 14 December 2022.

Further reading[edit]

External links[edit]