Yreka Fish and Wildlife Office
California and Nevada Region
Other Botanical Species

If you are unable to access any of the information contained on our site, please contact us. Your request will be referred to the appropriate program for assistance. Please indicate the nature of the accessibility need, your preferred format (electronic format, print, etc.) the web address of the requested material, and your full contact information so we can reach you if questions arise while fulfilling your request.

Our contact mailing address:

U.S. Fish and Wildlife Service
Yreka Fish and Wildlife Office
1829 S. Oregon Street
Yreka, California 96097
Phone: 530-842-5763
Fax: 530-842-4517
Email: yreka@fws.gov

Siskiyou Mariposa Lily

The Siskiyou Mariposa Lily (Calochortus persistens) is a Federal Candidate species.  Candidate species are those for which the Service has on file sufficient information on biological vulnerablility and threats to support proposals to list them as endangered or threatened.   This small lily is known from two populations and consists only of a few thousand plants on Federal and private land in northern California and southern Oregon.  The plant stands four to six inches high, with a short, unbranched stem.  A single grey-green, strap-shaped leaf appears to emerge directly from the ground.  Similar to a tulip, the Siskiyou Mariposa Lily produces one to three pink to lavender, three-petaled, cup shaped flowers; the inner and lower portion of the petals are yellowish and covered with gold hairs.

siskiyou mariposa lily
© 1983 Steve Lowens
siskiyou mariposa lily
© 1982 Steve Lowens

The Siskiyou Mariposa Lily is one of many endemic species found in the Klamath Siskiyou mountain region.  Suitable habitat for this perennial herb is found in open-shrub communities, in shallow metamorphic soils on exposed ridgetops, rocky outcrops, and talus slopes.  One of the two populations is found along a ridge which has one of the highest rates of lightning strikes in the area, suggesting that fire may be an important factor for this species.  This species shows characteristics of being long-lived with a slow growth rate and low rate of reproduction.

Threats to this species include its restricted range, predation of leaves, buds, flowers, and fruits by deer and insects, competition from exotic invasive species (especially Dyer’s woad or Marlahan mustard), lack of adequate regulatory mechanisms, mechanical disturbance, and changes to natural fire regimes. C. persistens is considered a rare species in California and is designated as a Sensitive Species by the U. S. Forest Service.

Slender Orcutt Grass

The slender Orcutt grass (Orcuttia tenuis) is one of eight other vernal pool-associated plants listed under the ESA (Federal Register Vol. 62, No. 58). Vernal pools in California are generally small, seasonally aquatic ecosystems that are inundated in the winter and dry slowly in the spring and summer, creating unusual ecological conditions supporting unique biota.  Once wide-spread in California, vernal pools have been significantly reduced due to urbanization and agriculture over the last two hundred years; therefore, most species associated with these habitats are considered at risk. O. tenuis is an annual grass that grows about two to six inches in height, and is described as being “weakly-tufted and sparsely-pilose”.

slender orcutt grass
© 1991 Dean Wm. Taylor
slender orcutt grass
© 2000 Robert E. Preston, Ph.D.

In northern California, vernal pools are often found on remnant alluvial fans, high stream terraces and recent basalt flows.  Disjunct populations of O. tenuis occur in these pools in Tehama, Lake, Lassen, Plumas, Sacramento, Shasta, and Siskiyou counties.  Two known populations occur on Federal and private land in southern Siskiyou County.

Critical habitat for slender Orcutt grass was originally designated in a final rule published in 68 FR 46683 on August 6, 2003. Economic exclusions from the 2003 final rule were evaluated in 70 FR 46923; published on August 11, 2005. Administrative revisions with species-by-unit designations were published in 71 FR 7117 on February 10, 2006, providing six critical habitat units (with 19 subunits) totaling 38,127 hectares (94,213 acres).

Forest Resources Main
Last updated: October 16, 2008