''Cupressus arizonica'', the Arizona cypress, is a North American

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriat ...

of tree in the cypress family Cupressaceae,

native Native may refer to: People * Jus soli, citizenship by right of birth * Indigenous peoples, peoples with a set of specific rights based on their historical ties to a particular territory ** Native Americans (disambiguation) In arts and entert ...

to the southwestern United States and Mexico. Populations may be scattered rather than in large, dense stands.

Description

''Cupressus arizonica'' is a

conifer Conifers are a group of cone-bearing seed plants, a subset of gymnosperms. Scientifically, they make up the division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single extant class, Pinopsida. All ext ...

ous

evergreen In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing season. This also pertains to plants that retain their foliage only in warm climates, and contrasts with deciduous plants, whic ...

tree with a

conic In mathematics, a conic section, quadratic curve or conic is a curve obtained as the intersection of the surface of a cone with a plane. The three types of conic section are the hyperbola, the parabola, and the ellipse; the circle is a specia ...

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 ''Glaucous'' (, ) is used to describe the pale grey or bluish-green appearance of the surfaces of some plants, as well as in the names of birds, such as the glaucous gull (''Larus hyperboreus''), glaucous-winged gull (''Larus glaucescens''), ...

blue-green. The leaves are scale-like, 2–5 mm long, and produced on rounded (not flattened) shoots. The seed cones are

globose A sphere () is a geometrical object that is a three-dimensional analogue to a two-dimensional circle. A sphere is the set of points that are all at the same distance from a given point in three-dimensional space.. That given point is the c ...

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 A wildfire, forest fire, bushfire, wildland fire or rural fire is an unplanned, uncontrolled and unpredictable fire in an area of combustible vegetation. Depending on the type of vegetation present, a wildfire may be more specifically identi ...

or otherwise), allowing the

seed A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiosper ...

s 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 Variety may refer to: Arts and entertainment Entertainment formats * Variety (radio) * Variety show, in theater and television Films * ''Variety'' (1925 film), a German silent film directed by Ewald Andre Dupont * ''Variety'' (1935 film), ...

are distinguished by some botanists, and these are sometimes treated as distinct species: * ''Cupressus arizonica'' var. ''arizonica'', Arizona Cypress – secure. Southern Arizona, southwest New Mexico, south to Durango and Tamaulipas, Chisos Mountains of west Texas. * ''Cupressus arizonica'' var. ''glabra'', Smooth Arizona cypress – secure. Central Arizona. * ''Cupressus arizonica'' var. ''montana'' (''C. montana''), San Pedro Mártir cypress – Vulnerable. Sierra Juárez and San Pedro Mártir pine–oak forests of Northern Baja California. * ''Cupressus arizonica'' var. ''nevadensis'' (''C. nevadensis''), Paiute cypress – Least Concern. Southern California (

Kern County Kern County is a county located in the U.S. state of California. As of the 2020 census, the population was 909,235. Its county seat is Bakersfield. Kern County comprises the Bakersfield, California, Metropolitan statistical area. The county sp ...

and Tulare County). * ''Cupressus arizonica'' var. ''stephensonii'', Cuyamaca cypress – Critically endangered. Southern California (

San Diego County San Diego County (), officially the County of San Diego, is a county in the southwestern corner of the U.S. state of California. As of the 2020 census, the population was 3,298,634, making it California's second-most populous county and the f ...

). Also known as ''Hesperocyparis stephensonii'' (Jespon Manual). Most of this population was burnt in the October 2003 Cedar Fire, though (as expected for a fire-climax species) subsequent regeneration has been good.

Distribution

''Cupressus arizonica'' is found mainly in the southwestern United States (

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...

Utah Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to its ...

, southwestern

New Mexico ) , population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano) , seat = Santa Fe, New Mexico, Santa Fe , LargestCity = Albuquerque, New Mexico, Albuquerque , LargestMetro = Albuquerque metropolitan area, Tiguex , Offi ...

, and southern

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...

, with a few populations in southern

Nevada Nevada ( ; ) is a U.S. state, state in the Western United States, Western region of the United States. It is bordered by Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. N ...

and in the

Chisos Mountains The Chisos Mountains, also known as the Chisos, are a mountain range located in the Big Bend area of the Trans-Pecos region of Texas, United States. The mountain system covers 40 square miles (104 square km) and is contained entirely within the ...

of western

Texas Texas (, ; Spanish: ''Texas'', ''Tejas'') is a state in the South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2020, it is the second-largest U.S. state by ...

), and in Mexico (

Coahuila Coahuila (), formally Coahuila de Zaragoza (), officially the Free and Sovereign State of Coahuila de Zaragoza ( es, Estado Libre y Soberano de Coahuila de Zaragoza), is one of the 32 states of Mexico. Coahuila borders the Mexican states of N ...

Nuevo León Nuevo León () is a state in the northeast region of Mexico. The state was named after the New Kingdom of León, an administrative territory from the Viceroyalty of New Spain, itself was named after the historic Spanish Kingdom of León. Wit ...

Chihuahua Chihuahua may refer to: Places * Chihuahua (state), a Mexican state **Chihuahua (dog), a breed of dog named after the state **Chihuahua cheese, a type of cheese originating in the state **Chihuahua City, the capital city of the state **Chihuahua Mu ...

Sonora Sonora (), officially Estado Libre y Soberano de Sonora ( en, Free and Sovereign State of Sonora), is one of the 31 states which, along with Mexico City, comprise the Federal Entities of Mexico. The state is divided into 72 municipalities; the ...

Durango Durango (), officially named Estado Libre y Soberano de Durango ( en, Free and Sovereign State of Durango; Tepehuán: ''Korian''; Nahuatl: ''Tepēhuahcān''), is one of the 31 states which make up the 32 Federal Entities of Mexico, situated in ...

Tamaulipas Tamaulipas (), officially the Free and Sovereign State of Tamaulipas ( es, Estado Libre y Soberano de Tamaulipas), is a state in the northeast region of Mexico; one of the 31 states which, along with Mexico City, comprise the 32 Federal Entiti ...

Zacatecas , image_map = Zacatecas in Mexico (location map scheme).svg , map_caption = State of Zacatecas within Mexico , coordinates = , coor_pinpoint = , coordinates_footnotes = , subdivision_type ...

and northern

Baja California Baja California (; 'Lower California'), officially the Free and Sovereign State of Baja California ( es, Estado Libre y Soberano de Baja California), is a state in Mexico. It is the northernmost and westernmost of the 32 federal entities of Mex ...

). 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 ''Quercus chrysolepis'', commonly termed canyon live oak, canyon oak, golden cup oak or maul oak, is a North American species of evergreen oak that is found in Mexico and in the western United States, notably in the California Coast Ranges. This ...

and

California fan palm ''Washingtonia filifera'', the desert fan palm, California fan palm, or California palm,Flora of North America Association. ''Flora of North America: North of Mexico Volume 22: Magnoliophyta: Alismatidae, Arecidae, Commelinidae (in Part), and Zi ...

Uses

Arizona cypress, particularly the strongly

''C. arizonica'' var. ''glabra'', is widely cultivated as an ornamental tree. Unlike

Monterey cypress ''Hesperocyparis macrocarpa'' is a coniferous tree. It is commonly known as the Monterey cypress and is one of several species of cypress trees endemic to California. The Monterey cypress is found naturally only on the Central Coast of Califor ...

, it has proved highly resistant to

cypress canker Cypress canker is a disease affecting ''Cupressus'' species, caused by one of several species of fungus in the genus ''Seiridium''. Infection causes die-back of twigs and branches in susceptible cypress trees, with rapidly increasing amounts of d ...

, caused by the fungus ''

Seiridium ''Lepteutypa'' is a genus of plant pathogens in the family Amphisphaeriaceae. First described by the Austrian mycologist Franz Petrak in 1923, the genus contains 10 species according to a 2008 estimate. The genus ''Lepteutypa'' is teleomorphic ...

cardinale'', and growth is reliable where this disease is prevalent. The

cultivar A cultivar is a type of cultivated plant that people have selected for desired traits and when propagated retain those traits. Methods used to propagate cultivars include: division, root and stem cuttings, offsets, grafting, tissue culture ...

'Pyramidalis' has gained the

Royal Horticultural Society The Royal Horticultural Society (RHS), founded in 1804 as the Horticultural Society of London, is the UK's leading gardening charity. The RHS promotes horticulture through its five gardens at Wisley (Surrey), Hyde Hall (Essex), Harlow Carr (Nor ...

Award of Garden Merit The Award of Garden Merit (AGM) is a long-established annual award for plants by the British Royal Horticultural Society (RHS). It is based on assessment of the plants' performance under UK growing conditions. History The Award of Garden Merit ...

(confirmed 2017).

Example of neoendemism and conservation challenges

The ease of

hybridization Hybridization (or hybridisation) may refer to: *Hybridization (biology), the process of combining different varieties of organisms to create a hybrid *Orbital hybridization, in chemistry, the mixing of atomic orbitals into new hybrid orbitals *Nu ...

cypress Cypress is a common name for various coniferous trees or shrubs of northern temperate regions that belong to the family Cupressaceae. The word ''cypress'' is derived from Old French ''cipres'', which was imported from Latin ''cypressus'', the l ...

species in the

American southwest The Southwestern United States, also known as the American Southwest or simply the Southwest, is a geographic and cultural region of the United States that generally includes Arizona, New Mexico, and adjacent portions of California, Colorado ...

has fostered a parallel history of taxonomic disagreements of where genus and species distinctions should apply. It thus provides a case study of

neoendemism Neoendemism is one of two sub-categories of endemism, the ecological state of a species being unique to a defined geographic location. Specifically, neoendemic species are those that have recently arisen, through divergence and reproductive isola ...

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

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'')
* {{Taxonbar, from=Q670040 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 Natural history of the Transverse Ranges Plants described in 1882 Taxa named by Edward Lee Greene Least concern flora of North America