S. Wats.
Identity
Unique IDELEMENT_GLOBAL.2.135629
Element CodePMLIL0D120
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicendemic to a single state or province
KingdomPlantae
PhylumAnthophyta
ClassMonocotyledoneae
OrderLiliales
FamilyLiliaceae
GenusCalochortus
Concept ReferenceKartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2026-03-20
Change Date2016-03-23
Edition Date2026-03-20
Edition AuthorsRusso, Mary (TNC WRO, 1989), rev. L. Oliver (2003), rev. Soteropoulos (2026)
Threat ImpactHigh
Range Extent20,000-200,000 square km (about 8000-80,000 square miles)
Number of Occurrences81 - 300
Rank ReasonsCalochortus palmeri is a perennial herb found in mesic habitats, in meadows, grassy knolls, seeps, as well as along creeks or swales, and vernally moist places in yellow pine forest, lower montane coniferous forest, pinyon woodland, and chaparral. It is endemic to the western United States in nine counties of southwestern California. There are an estimated 100 occurrences, which face threats from development, grazing, non-native species, recreational activities (including trampling by hikers and damage by off-road vehicles), road associated threats including maintenance, dozer lines, mining, altered hydrology, fuel treatments and fire salvage, logging, and pollution. Trends suggest a decline of over 30% of occurrences. Monitoring of populations should be conducted to improve our understanding of reproduction, plant abundance, threats, and trends, as well as continuing conservation measures to protect the taxon.
Range Extent CommentsCalochortus palmeri is endemic to the western United States in southwestern California, where it has been documented in Kern, Los Angeles, Riverside, San Bernardino, San Diego, San Luis Obispo, Santa Barbara, and Ventura counties (FNA 2002, CNPS 2026). Range extent was estimated to be 51,932 square kilometers using herbarium specimens and NatureServe Network occurrence data documented between 1994 and 2025 (RARECAT 2025, GBIF 2026, NatureServe 2026, SEINet 2026).
Occurrences CommentsBy applying a 1 km separation distance to herbarium specimens and NatureServe Network occurrence data documented between 1994 and 2025, it is estimated that there are approximately 100 occurrences rangewide (RARECAT 2025, GBIF 2026, NatureServe 2026, SEINet 2026).
Threat Impact CommentsThis taxon faces threats from development, grazing, non-native species (Bromus tectorum), recreational activities (including trampling by hikers and damage by off-road vehicles), road associated threats including maintenance, Dozer lines, mining, altered hydrology, fuel treatments and fire salvage, logging, and pollution.