Leaflets lanceolate (much longer than wide, wider toward base) to oblanceolate (lanceolate, but widest part is toward the tip), margins entire (smooth), ~0.4-1 cm long, medium green to bluish-silvery green, glabrous (smooth-surfaced). Very short petioles attach compound leaves to stems in an alternate arrangement, with each leaflet clearly separated from the next along the stem. Stems are glabrous or very softly hairy. Inflorescences are umbels (clusters of flowers radiating out from a central point) with 1-7 flowers forming along the outer stems. The umbels are almost always axial (coming out of leaf axils) and sessile (no peduncle or stalk). Individual flowers are sessile or nearly so. Flower calyxes (sepal structure under the corolla) have 5 fused sepals forming a cylindric or bell-shaped tube ~ 0.3 cm long. The bright yellow corolla is tubular, ~0.7-1.1 cm long, with 5 petals partially fused (2 on top forming an erect and steepled banner and 3 fused into a keel below, which is roughly in the same line as the corolla/calyx tube). New flowers are bright yellow, which then darkens to orange and red as the flowers age and new flowers develop farther out on the stem. Blooms March to August. Fruit is a slender glabrous (smooth) pod ~1.5 cm long, often curving, and tipped with an awl-shaped beak, containing 2-3 dark brown seeds. The plant is a branching perennial subshrub ~0.2 to 2 m tall, woody at the base, with slender and somewhat wand-like herbaceous green and well-branched stems. These may be erect or mostly ascending (though sometimes they can sprawl across the ground giving a matted appearance), slightly silky or pubescent. Species favors dry slopes, washes, and fans below 1500 m in California sage scrub, chaparral, the coastal strand from Del Norte County to Baja, and desert slopes in the northern and central Coast Ranges, the Transverse and Peninsular ranges, the Sierra foothills in the Sacramento Valley, and the Colorado/Sonoran Desert into Arizona and northern Mexico. It is tolerant of disturbed habitat, such as roadsides and recently burned areas. Locally, this species is critical habitat for the larv&alig; of the Palos Verdes Blue Butterfly (Glaucopsyche lygdamus palosverdesensis).
Lotus scoparius (Fabaceae): deerweed or California broom
The development of this key was partially funded through the Geoscience Diversity Enhancement Program (Award #0703798) and through a course of re-assigned time provided by the CSULB Scholarly and Creative Activities Committee. Thanks also to the students in sections of biogeography, introductory physical geography, GDEP, and LSAMP for "test-driving" various editions of this key.