South Coast Saltscale [Atriplex pacifica Nels.]

South Coast Saltscale [Atriplex pacifica Nels.]

Listing CNPS List 1B R-E-D Code 3-2-2

State/Federal. Status -- /C2 CHENOPODIACEAE Mar.-Oct.

Global Rank G3? State Rank S2.2

Distribution: San Diego County, Orange County, Los Angeles County, Ventura County, Riverside County, San Clemente Island, Anacapa Island, Santa Catalina Island, Santa Cruz Island, San Nicolas Island, and Santa Rosa Island; Baja California and Sonora, Mexico

Habitat: This wiry little herb grows in xeric, often mildly disturbed locales. Soils are mapped as Linne clay loam at the Rice Canyon site and Huerhuero-urban land complex in Imperial Beach. Usually the surrounding vegetation is an open Diegan Sage Scrub dominated by Artemisia californica; although, near the Bernasconi Hills it was found on alkaline flats in an area devoid of taller shrubs.

Known Sites: The type specimen for this little saltbush is from San Diego; presumably within several miles of the ocean. Sites include small populations seen just east of Fairbanks Ranch near Lusardi Canyon along a pipeline easement, in Chula Vista's Rice Canyon near an expanding new housing development, in Salt Creek near the aquaduct crossing north of Otay Mesa, on the periphery of the salt marsh near the mouth of the Tijuana River in Imperial Beach, near the northern terminus of Dillon Road on Otay Mesa, and in western Riverside County south of the Bernasconi Hills and the Ramona Expressway growing with Atriplex coronata var. notatior. These small populations are all endangered by foot traffic or development. A sizeable population is scattered in the grasslands and around the salt pannes southwest of Florida and Warren Roads in Hemet in Riverside County. Roberts reports this species from Orange County where possibly no longer extant. A herbarium specimen was examined from the San Pedro Hills of Los Angeles County. It is reported from San Clemente Island, Santa Catalina Island, and Santa Rosa Island.

Twenty-four herbarium specimens from Baja California were examined at the San Diego Natural History Museum. A small population was found close to the U.S. border in Baja California, near the highway west of Tecate and the new prison. A second site was examined east of Valle de las Palmas on a flat mesa among numerous vernal pools. It is locally common on the seabluffs between La Fonda and Punta Mesquite; typically growing within twenty yards of the cliffs. Also found at SD is a herbarium specimen from the Pinacate region of Sonora.

Status: South Coast Saltscale is apparently severely declining throughout its coastal range on the mainland. Until more thorough information is available on the cumulative populations of Pacific Saltbush, all mainland populations should be protected. Although detailed horticultural requirements are poorly known, this species can apparently be grown from seed, and new populations should be established in appropriate native habitat.

Parish's Brittlescale (Atriplex parishii Wats.

Listing CNPS List 1B R-E-D Code 3-2-2

State/Federal. Status -- None CHENOPODIACEAE Jun.-Oct.

Global Rank G2? State Rank S1.1

Distribution: Riverside County, San Diego County, Los Angeles County, Orange County, San Bernardino County; Baja California

Habitat: This species grows in alkaline flats on the periphery of salt pannes. The few extant locales where recently observed occur in flat terrain which has been historically grazed and which can be quite mesic in the spring following heavy rainfall. A variety of other sensitive plants such as Atriplex coronata var. notatior share its habitat near Hemet.

Known Sites: This saltbush is very rare in fields near California Street on the western outskirts of Hemet, Riverside County; it is also reported along the nearby San Jacinto River floodplain south of the Bernasconi Hills.

Status: Parish's Brittlescale is likely extirpated from most of its historical locales. All populations should be protected and it is a possible candidate for federally endangered status. No San Diego County herbarium specimens have been located.

Davidson's Saltscale (Atriplex serenana A. Nels. var davidsonii (Standl.) Munz

Listing CNPS List 1B R-E-D Code 3-2-2

State/Federal. Status -- None CHENOPODIACEAE Apr.-Oct.

Global Rank G5T2? State Rank S2?

Distribution: Riverside County, San Diego County, Los Angeles County, Orange County, Santa Barbara County, Ventura County, Santa Rosa Island; Baja California, Mexico

Habitat: This species grows in semi-alkaline swales and seems to be able to tolerate limited disturbance based on a site with a robust population near Tres Cerritos. It is difficult to account for its rarity; the related variety serenana is an aggressive weed with markedly longer leaves. Davidson's Saltscale may have historically been associated with the isolated alkaline flats of Southern California valleys; areas which have primarily been drained and converted to residential housing or agriculture.

Known Sites: This saltscale is abundant along a disturbed swale adjacent to Menlo Avenue on the southeastern corner of Tres Cerritos near Lakeview, Riverside County. It is reported by Munz for coastal areas from Low Angeles to Balboa and Laguna Beach. It may no longer be extant at most historic locales where once collected, in this now heavily urbanized region. Herbarium specimens from the San Diego Natural History Museum include vouchers from the San Pasqual Valley and the Sweetwater River near San Miguel Mountain which roughly conform to the description of variety davidsonii. Another specimen from San Diego County in the lower Tijuana River has longer leaves and may represent variety serenana.

Status: Davidson's Saltscale may be extirpated from San Diego County and is apparently extremely rare in the Los Angeles basin based on the few known extant locales. It is presumed to be severely declining throughout its range, and Davidson's Saltscale may be close to extinction. Taxonomic work is necessary to more clearly delineate it from the related and relatively common Atriplex serenana var. serenana. All populations should be protected. Although detailed horticultural requirements are poorly known, seed is abundant on the plants observed in the field. Seed should be collected and attempts made to grow this plant under controlled nursery conditions, with a goal of later establishment in suitable native habitat.


Copyright May 1994 Craig H. Reiser.

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