Cliff Spurge [Euphorbia misera Benth.]
Listing CNPS List 2 R-E-D Code 2-2-1
State/Federal. Status -- None EUPHORBIACEAE Jan.-Aug.
Global Rank G5 State Rank S3.2
Distribution: San Diego County, Orange County, Riverside County, San Clemente Island; Baja California, Mexico
Habitat: A Maritime Sage Scrub with a high incidence of cactus is typical of the preferred habitat for Cliff Spurge. Usually the scrub is quite low-growing and windswept near the beach; movement throughout this habitat is not difficult. Olivenhain cobbly loam is utilized on Otay Mesa; Gaviota fine sandy loam is found at Point Loma.
Known Sites: Outstanding populations are found at the Naval Subase and Cabrillo National Monument on Point Loma. An excellent stand grows on south-facing slopes of Dillon Canyon on Otay Mesa; as well as in Spring Canyon to the east of Bolton Hall Road near San Ysidro. This low-growing shrub is also found on the west-facing slopes of Spooner's Mesa near the Mexican border. An old report, where possibly no longer extant, is on a hillside overlooking a slough at Carlsbad. Old biological survey reports note sites in Moody Canyon on Otay Mesa, in Spring Canyon on Otay Mesa, west of the Salk Institute in La Jolla; as well as north of the San Dieguito River and south of Via de la Valle on a bluff overlooking the Fairbanks County Club. Another old report is from Jaeger on the Colorado Desert near the historic boundary of Lake Cahuilla. Cliff Spurge is localized on the bluffs at the headlands on Dana Point in Orange County. Roberts reports two small Orange County populations on beach bluffs in Corona Del Mar. It is also reported on the sea bluffs at San Clemente Island.
Seventy-seven herbarium specimens from Baja California are found at the San Diego Natural History Museum south to 27 29' North where collected by Moran(SD 115893), west of Volcan tres Virgenes; also on islands to the south. It is locally common in Baja California on ocean bluffs from Rosarito Beach south to the Ensenada region, as at La Fonda and Baja Del Mar, and is widespread on Punta Banda.
Status: Cliff Spurge populations in the United States are stable. Future expansion of the Naval Subase at Point Loma could impact the local population. Widespread development on Otay Mesa which has escalated following rezoning of the area could impact canyon populations. It is presumed that most United States populations of Cliff Spurge have already been discovered, as such, it is recommended that all populations be protected.
Copyright © May 1994 Craig H. Reiser.