[Wikipedia] Range, Elevation Range: It is native to the hills and mountains of southern California and Baja California, where it grows in shady areas in clay soils at elevations up to 800 m. The species has been reported from Kern, San Bernardino, Los Angeles, Riverside, Santa Barbara, Orange and San Diego Counties. This includes some populations on the Channel Islands.[1][2] (link added by Mary Ann Machi)