Hesperocyparis nevadensis

(Abrams) Bartel

Paiute Cypress

G2Imperiled Found in 4 roadless areas NatureServe Explorer →
G2ImperiledGlobal Rank
EndangeredIUCN
MediumThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.140811
Element CodePGCUP04012
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
IUCNEndangered
Endemicendemic to a single state or province
KingdomPlantae
PhylumConiferophyta
ClassPinopsida
OrderPinales
FamilyCupressaceae
GenusHesperocyparis
Synonyms
Callitropsis nevadensis(Abrams) D.P. LittleCupressus arizonica ssp. nevadensis(Abrams) E. MurrayCupressus arizonica var. nevadensis(Abrams) LittleCupressus nevadensisAbrams
Other Common Names
Paiute cypress (EN)
Concept Reference
Kartesz, J.T. 1999. A synonymized checklist and atlas with biological attributes for the vascular flora of the United States, Canada, and Greenland. First edition. In: Kartesz, J.T., and C.A. Meacham. Synthesis of the North American Flora, Version 1.0. North Carolina Botanical Garden, Chapel Hill, N.C.
Taxonomic Comments
Hesperocyparis nevadensis is considered a distinct species by Little (2006) and Adams et al. (2009) but a subspecies of Cupressus arizonica by Kartesz (1999). Little (2006) transferred all Western Hemisphere Cupressus to the genus Callitropsis and Adams et al. (2009) further isolated the Western Hemisphere cypress lineage into a new genus Hesperocyparis. Little (2006) and Adams et al. (2009) considered the following distinct from Hesperocyparis arizonica: Hesperocyparis glabra (syn. Callitropsis glabra, Cupressus arizonica ssp. glabra, Cupressus glabra), Hesperocyparis nevadensis (syn. Callitropsis nevadensis, Cupressus arizonica ssp. nevadensis, Cupressus nevadensis), and Hesperocyparis stephensonii (syn. Callitropsis stephensonii, Cupressus arizonica ssp. stephensonii, Cupressus stephensonii), which Flora of North America (1993, vol. 2) include in synonymy.
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2023-07-28
Change Date1999-07-21
Edition Date2023-07-28
Edition AuthorsOgle, Y. (1987), rev. Bittman (2017), rev. Eberly (2023)
Threat ImpactMedium
Range Extent250-1000 square km (about 100-400 square miles)
Number of Occurrences6 - 20
Rank Reasons
This taxon is endemic to California in the western United States. It is a narrow endemic found in Kern and Tulare Counties with most groves in the Piute and Greenhorn Mountains bordering the Kern River Valley. There are less than 20 occurrences that are threatened by an increase in fire frequency, grazing, mining, and recreational activities.
Range Extent Comments
This taxon is endemic to California in the western United States. It is found in Kern and Tulare Counties (CNDDB 2023). Most groves are located in the Piute and Greenhorn Mountains which border the Kern River Valley (Bartel 2019).
Threat Impact Comments
This species occurs in fire prone areas and has serotinous cones; it relies on low exposure to low intensity fire to open the cones but high intensity fires may reduce germination rates (Milich 2010). Too frequent fires, occurring less than 20 or 30 years apart, may be detrimental to populations, as trees are typically killed by fire and the next generation of sapling doesn't reach sexual maturity until they are 6 to13 years old (Bartel 2019). Fire suppression may also be a threat, as it would also minimize germination events and allow for the expansion of chaparral shrubs. This species is potentially threatened by grazing, mining, and recreational activities (CNDDB 2023).
Ecology & Habitat

Habitat

This taxon grows on dry slopes in closed-cone coniferous forest, chaparral, cismontane woodland, pinyon and juniper woodland and woodland ecotones at elevations of 715 to 1,585 m (Jepson Flora Project 2023, CNDDB 2023). It can occur on a variety of substrates including granite, granodiorite, and gabbro and metasedimentary rocks like micaceous schist, quartzite, and limestone (Bartel 2019).

Ecology

Trees do not typically survive fires, but the three canopy holds a seed bank that is released by fire from serotinous cones. Without exposure to fire, trees can live to be hundreds of years old (Bartel 2019).
Terrestrial Habitats
Forest - ConiferWoodland - ConiferWoodland - MixedShrubland/chaparral
Other Nations (1)
United StatesN2
ProvinceRankNative
CaliforniaS2Yes
Threat Assessments
ThreatScopeSeverityTiming
2 - Agriculture & aquacultureLarge (31-70%)UnknownHigh (continuing)
2.3 - Livestock farming & ranchingLarge (31-70%)UnknownHigh (continuing)
3 - Energy production & miningRestricted (11-30%)UnknownHigh (continuing)
3.2 - Mining & quarryingRestricted (11-30%)UnknownHigh (continuing)
6 - Human intrusions & disturbanceSmall (1-10%)UnknownHigh (continuing)
6.1 - Recreational activitiesSmall (1-10%)UnknownHigh (continuing)
7 - Natural system modificationsRestricted (11-30%)Extreme - seriousHigh (continuing)
7.1 - Fire & fire suppressionRestricted (11-30%)Extreme - seriousHigh (continuing)
7.1.1 - Increase in fire frequency/intensityRestricted (11-30%)Extreme - seriousHigh (continuing)
7.1.2 - Suppression in fire frequency/intensityRestricted (11-30%)UnknownHigh (continuing)

Plant Characteristics
DurationPERENNIAL, Long-lived, EVERGREEN
Economic Value (Genus)No
Roadless Areas (4)
California (4)
AreaForestAcres
ChicoSequoia National Forest39,836
Greenhorn CreekSequoia National Forest28,226
Mill CreekSequoia National Forest27,643
WoolstaffSequoia National Forest41,445
References (7)
  1. Adams, R.P., J.A. Bartel, and R.A. Price. 2009. A new genus, <i>Hesperocyparis</i>, for the Cypresses of the Western Hemisphere (Cupressaceae). Phytologia 91(1):160-185.
  2. Bartel, J.A. 2019. Piute cypress: An intriguing past and uncertain future. Fremontia 47(1): 23-28.
  3. California Natural Diversity Database (CNDDB). 2023. RareFind Version 5.2.14. California Department of Fish and Game, Sacramento.
  4. Jepson Flora Project (eds.) 2023. Jepson eFlora. Online. Available: https://ucjeps.berkeley.edu/eflora/ (accessed 2023).
  5. Kartesz, J.T. 1999. A synonymized checklist and atlas with biological attributes for the vascular flora of the United States, Canada, and Greenland. First edition. In: Kartesz, J.T., and C.A. Meacham. Synthesis of the North American Flora, Version 1.0. North Carolina Botanical Garden, Chapel Hill, N.C.
  6. Little, E.L., Jr. 1979. Checklist of United States trees (native and naturalized). Agriculture Handbook No. 541. U.S. Forest Service, Washington, D.C. 375 pp.
  7. Milich, K.L. 2010. Cone serotiny and seed viability of fire-prone California Cupressus species. M.S. thesis. Humboldt State University, Arcata, California.