Regularity: Regularly occurring
Global Range: Endemic to California; Santa Cruz Mnts., Bonnie Doon, Eagle Rock and vicinity of Boulder Ck., Santa Cruz Co., and Butano Ridge, San Mateo Co., California.
Habitat and Ecology
Comments: Associated with coastal chaparral communities above the fog belt at 300-760 m. Some groves contain yellow pine and closed-cone pine forest elements. Soils are typically shallow, very well drained sands and sandy-gravelly loams which are low in nutrients. Fire or other disturbance that exposes bare mineral soil may enhance the rate of seedling establishment.
Molecular Biology and Genetics
Barcode data: Hesperocyparis abramsiana
Statistics of barcoding coverage: Hesperocyparis abramsiana
Public Records: 4
Specimens with Barcodes: 4
Species With Barcodes: 1
IUCN Red List Assessment
Red List Category
Red List Criteria
- 1997Endangered(Walter and Gillett 1998)
National NatureServe Conservation Status
Rounded National Status Rank: N1 - Critically Imperiled
NatureServe Conservation Status
Rounded Global Status Rank: G1 - Critically Imperiled
Reasons: Known from fewer than 10, relatively isolated populations, all located in the Santa Cruz Mountains of California. There are about 5,100 individuals occupying a total of about 142 ha. There are no imminent threats from habitat alteration or destruction, but the species is somewhat threatened by disruption of natural fire cycles, introgression with other species of cypress, and the potential for oil and gas drilling.
Date Listed: 01/08/1987
Lead Region: California/Nevada Region (Region 8)
Listing status: E
For most current information and documents related to the conservation status and management of Cupressus abramsiana, see its USFWS Species Profile
Fire is a threat to this species: subpopulations are all found in dry forest ecosystems associated with high fire risk chaparral habitats.Increased human pressures through development has direct impact through forest clearance, and indirect impacts through fire management (prevention and extinguishing), which benefits Pinus spp. and allows these larger conifers to outcompete Cupressus arizonica var. abramsiana.
Degree of Threat: Very high - medium
Comments: In 1987, this species faced many threats including development, conversion of land for agricultural purposes, and frequent burning. Other threats include logging, vandalism, genetic introgression, and alteration of natural fire regimes. One grove also was threatened by oil and gas drilling (USFWS 1987). A recovery plan was created for this species that updated the threats to this species in 1998. The grove that was threatened by gas and oil drilling is less threatened by these activties because the drilling attempts failed and the operation was abandoned. Any future drilling efforts are to be coordinated by the BLM, but drilling is not currently a threat. Also, since 1975 no further development has taken place near or on land that the species occupies, however, indirect threats due to surrounding housing does exist. These indirect threats are soil erosion, wood cutting, insect infestation and invasion of non-native species. Timber harvesting may be less of a threat as the timber company is aware of the rare species, however, indirect effects of nearby harvesting may cause wind and water erosion. Another grove that was in danger of being converted into a vineyard, is now protected as The Nature Conservancy bought the property in 1989, which was then deeded to the California Department of Fish and Game as an ecological preserve. Other threats such as alteration of fire regimes still threaten (USFWS 1998).
The largest subpopulation is partly found within the Bonnie Doon National Reserve, however, the remaining subpopulations are outside any protected areas.Conservation actions should aim to prevent increased pressure from urban development and manage fire risks in a way that does not in the long term disadvantage this taxon.
Biological Research Needs: Ecological factors affecting this species, especially the effects of fire on populations, species biology, taxonomic study, smog effects.
Cupressus abramsiana (Santa Cruz Cypress) is a cypress taxon of disputed status, placed in either the genus Cupressus or else Xanthocyparis. It is endemic to the Santa Cruz Mountains of Santa Cruz and San Mateo Counties in west-central California.
When cypresses were discovered in the Santa Cruz Mountains in 1881, they were first identified as Cupressus goveniana, but Jepson (1909) considered them to be Cupressus sargentii. In a detailed analysis, Wolf (1948) concluded it was a distinct species, naming it after L. R. Abrams, Emeritus Professor of Botany at Stanford University.
Subsequent authors have either followed Wolf in treating it as a species (Griffin & Critchfield 1976, the 1993 edition of the Jepson Manual, and Lanner 1999), or within Cupressus goveniana as either a variety (Cupressus goveniana var. abramsiana (C.B.Wolf) Little; as in Little (1970), the Gymnosperm Database and Farjon (2005)), or not distinguished at all within C. goveniana (Flora of North America)
Santa Cruz cypress is a small evergreen tree growing to 10 m (rarely to 25 m) tall. The bark is gray, with a fibrous stringy texture, shredding on old trees. The foliage is bright green to yellowish-green, with scale-like leaves 1-1.5 mm long, the leaf tips slightly spreading on vigorous shoots but not on small shoots. Seedlings bear needle-like leaves 8-10 mm long. The cones are ovoid, 20-30 mm long and 15-22 mm broad, with eight or ten scales arranged in opposite decussate pairs, with the bract visible as no more than a small lump or short spine on the scale. The seeds are 3-5 mm long, glaucous brown, with a pair of small wings along the sides. The cones remain closed on the trees for many years, until the trees are killed by a forest fire; after the tree is dead, the cones open to release the seeds which can then germinate successfully on the bare fire-cleared ground.
It is in some respects intermediate between Cupressus goveniana and Cupressus sargentii in morphology, and two studies have suggested (without conclusive proof) that it could be a natural hybrid between the two.
It is rare in the wild, found in only five small localities in Santa Cruz County, California, and is listed as endangered. It is separated from Cupressus goveniana in Monterey County by a gap of about 50 km, and from the also closely related Cupressus pigmaea by a gap of about 200 km. It grows at 460-1200 m altitude, much higher than either C. goveniana or C. pigmaea.
- Wolf, C. B. & Wagener, W. E. (1948). The New World Cypresses. El Aliso 1: 215-222.
- Griffin, J. R., & Critchfield, W. B. (1976). The Distribution of Forest Trees in California. USDA Forest Service Research Paper PSW-82.
- Cupressus abramsiana in the Jepson Manual, University of California Press (1993)
- Lanner, R. M. (1999). Conifers of California. Cachuma Press. ISBN 0-9628505-3-5
- Little, E. L. (1970). Names of New World Cypresses (Cupressus). Phytologia 20: 429-445.
- Gymnosperm Database
- Farjon, A. (2005). A Monograph of Cupressaceae and Sciadopityaceae. Royal Botanic Gardens, Kew. ISBN 1-84246-068-4.
- Eckenwalder, J. E., in Flora of North America
- McMillan, C. (1951). A third locality for Cupressus abramsiana Wolf. Madroño 11: 189-194.
- Zavarin, E., Lawrence, L., & Thomas, M. C. (1971). Compositional variations of leaf monoterpenes in Cupressus macrocarpa, C. pygmaea, C. goveniana, C. abramsiana and C. sargentii. Phytochemistry 10: 379-393.
- IUCN status report.
Names and Taxonomy
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