Endangered Species Recovery Program
Bakersfield smallscale has an upright stem and a few stiff branches that are covered with white scales and have red tips. The leaves, which are lance- or egg-shaped, are opposite on at least the lower part of the stem. Both male and female flowers occur in leaf axils throughout the plant. The reddish-brown seeds are enclosed in diamond-shaped bracts that are smooth on the surface but toothed on the margin.
Bakersfield smallscale is a summer annual, germinating from May to June and flowering from June to October. Surface soil moisture is required during the summer and fall months for seed germination, seedling survival, and reproduction. Other aspects of the life history and reproductive biology are unknown.
All the populations of Bakersfield smallscale were found on the subalkaline margins of alkali sinks at elevations of 91-96 m. Associated species included alkali heath (Frankenia salina), glasswort (Salicornia subterminalis), scratchgrass (Muhlenbergia asperifolia), and saltgrass (Distichlis spicata).
Bakersfield smallscale was restricted historically to a small area of south-central Kern County between Greenfield and Mettler. Collection localities were Greenfield, Adobe Station, Adobe Road, and Highway 223.
The only site that still may support Bakersfield smallscale is a remnant of Kern Lake known as Gator Pond, formerly the Kern Lake Preserve. However, Bakersfield smallscale specimens collected in the area historically differ in appearance from those now present at Gator Pond.
Like many of the other endangered plants of the San Joaquin Valley, the decline of Bakersfield smallscale was due primarily to agricultural activities. At most of the historical locations of this species, the habitat was completely destroyed by cultivation. In addition, the lowering of the water table in the vicinity of Gator Pond led to conditions too dry for germination and survival of Bakersfield smallscale in all but the wettest years.
Subclass CARYOPHYLLIDAE, Order CARYOPHYLLALES, Family CHENOPODIACEAE, Genus Atriplex, Species tularensis
Freas, K.E., and D.D. Murphy. 1988. Taxonomy and the conservation of the critically endangered Bakersfield saltbush, Atriplex tularensis. Biol. Conserv. 46:317-324; Freas, K.E., and D.D. Murphy. 1991. The endangered Bakersfield saltbush. Fremontia 19(2):15-18; Taylor, D., and D.H. Wilken. 1993. Atriplex. Pp. 501-505 in The Jepson manual: higher plants of California (J.C. Hickman, ed.). Univ. California Press, Berkeley, 1400 pp.; Twisselmann, E.C. 1969. Status of the rare plants of Kern County. California Native Plant Soc. Newsletter 5(3):1-7; Skinner, M.W., and B.M. Pavlik, eds. 1994. I nventory of rare and endangered vascular plants of California. Fifth edition. Spec. Publ. No. 1, California Native Plant Society, Sacramento, 338 pp.; Rarefind, California Natural Diversity Database, Sacramento.
1 mm diameter
Bractscale (Atriplex serenana) is a related species that overlaps in range with Bakersfield smallscale. However, unlike Bakersfield smallscale, bractscale has toothed leaf margins, the male flowers occur only at the branch tips, and the fruiting bracts are wedge-shaped or round. Lesser saltscale (Atriplex minuscula) has many branches and the fruiting bracts are covered with tubercles (wart-like projections). Lost Hills crownscale (Atriplex vallicola) is distinguished from Bakersfield smallscale by the shape of the fruiting bracts and overall plant habit.
T.M. Sandoval and E.A. Cypher