Hesperocyparis nevadensis

Hesperocyparis nevadensis is a species of western cypress tree with the common name Paiute cypress native to a small area in the Sierra Nevada Mountains of California in the western United States. It was formerly known as Cupressus nevadensis.

Distribution
The Paiute cypress grows in a small area of the Southern Sierra Nevada, within Kern County, California and Tulare County. It is found on soils of granitic origin at altitudes of 3000 - 6000 ft. It is found in pinyon/juniper and oak/pine woodlands, chaparral, and closed-cone-cypress forest habitats. The largest grove composed primarily of the species is located south of the town of Bodfish in the Lake Isabella region. There are eight or so other populations of much smaller, scattered stands in the Southern Sierras.

Description
Hesperocyparis nevadensis is a medium-sized evergreen tree with a conic crown, growing to heights of 10–25 m (exceptionally to 39 m), and a trunk diameter of up to 0.5 m (exceptionally to 1 m). The foliage grows in sparse, very fragrant, sprays varying from dull gray-green to glaucous blue-green in color. The leaves are scale-like, highly glandular, resinous and aromatic, 2–5 mm long, and produced on rounded (not flattened) shoots.

The seed cones are globose to oblong, 25–55 mm long, with 6 or 8 (rarely 4 or 10) scales, green to brown at first, maturing gray or gray-brown about 20–24 months after pollination. The male cones are 3–5 mm long, and release pollen in February–March.

The cones often remain closed for several years, only opening after the parent tree is killed in a wildfire, thereby allowing the seeds to colonize the bare ground exposed by the natural fire.

Conservation
Like most California cypress, it is a pyrophyte, heavily reliant on wildfire for its regeneration. Fire suppression policies of the past decades have severely limited reproduction of this fire dependent species. It is on the IUCN Red List as an endangered species.

Taxonomy
It has been reclassified in the genus Hesperocyparis, with other former Cupressus species native to western North America. It was also previously included as a subspecies within Cupressus arizonica, Cupressus arizonica subsp. nevadensis. [http://plants.usda.gov/core/profile?symbol=HENE2 USDA: Hesperocyparis nevadensis synonyms; Cupressus arizonica subsp. nevadensis]. accessed 8.28.2015