Dwarf Pepper Grass [Lepidium latipes Hook. var. latipes]
Listing CNPS Unlisted R-E-D Code - None
State/Federal. Status -- None BRASSICACEAE Mar.-May
Global Rank None State Rank None
Distribution: San Diego County, Merced County, Colusa County, Marin County, Napa County, Santa Barbara County, Tehama County, Yolo County, San Clemente Island, Santa Cruz Island; Baja California, Mexico
Habitat: This miniscule annual in the Mustard Family grows on Terrace Escarpments within feet of beach bluffs at Camp Pendleton. Shrubs are not present here; vegetation consists of Eurasian grasses and a few vestigial native elements such as Dudleya blochmaniae. It has previously been reported in the region on the periphery of Southern Hardpan Vernal Pools.
Known Sites: Dwarf Pepper Grass may be extirpated from vernal pools on Otay Mesa. A small colony grows within yards of steep ocean bluffs south of Cocklebur Creek in Military Sector Victor on Camp Pendleton. A recent report is from vernal pools near the intersection of Calbaugh and Brea in Ramona. Reported by Thorne as rare and possibly extirpated on Santa Catalina Island. Reported by Thomas for the southern portion of San Francisco Bay and the Santa Clara Valley; also Mayfield 3 miles south of San Jose. Reported by Bowerman from Donner Canyon and a canyon south of Arroyo del Cerro near Mount Diablo.
Six specimens from Baja California are found at the San Diego Natural History Museum's herbarium; south to 31 51' North where collected by Moran (SD 105041) in a depression in a cleared field, 7 km southwest of Ojos Negros. It was observed in small numbers in a small roadside vernal pool near Los Hormos, south of the Guadalupe Valley on the old highway to Ensenada
Status: Dwarf Pepper Grass is almost extirpated in San Diego County. The one known extant locale at Camp Pendleton is precariously placed and will probably erode onto the beach below within the next decade or two; disturbed soils occur only yards to the east. Rare plant surveys in the fall and winter may not note this cryptic annual, even if it is present in limited numbers. This species was formerly listed by the CNPS, but has been deleted as too common within the northern portions of its range. It is quite rare in Southern California, where all populations should be fully protected. Given the considerable disjunction between the more substantial northern populations, and plants in the southern regions, taxonomic research is recommended to determine if the southern plants are similar to their northern counterparts, or if they may represent an as yet unidentified subspecies.
Copyright © May 1994 Craig H. Reiser.