Known from fewer than 10 occurrences, but population numbers are increasing. See Bulletin of the Southern California Academy of Sciences 41:130 (1943) for original description, and Phytologia 66(4):318-319 (1989) for taxonomic treatment.
California Native Plant Society (CNPS).
Inventory of Rare and Endangered Plants (online edition, v8-02).
California Native Plant Society. Sacramento, CA. Accessed on
.