Annuals; (somewhat glaucous), glabrous throughout. Stems branched distally, (1-)2-9 (-10.5) dm. Basal leaves not rosulate; petiolate; blade pinnatisect to pectinate into filiform segments, 2-8 cm. Cauline leaves (petiolate proximally, sessile distally); blade pectinate or pinnatisect into filiform segments, or (distally) linear-lanceolate to ovate or cordate, 2-12 cm, (segments 0.4-2.7 cm × 0.5-1.5 mm), base not auriculate proximally, amplexicaul distally, margins entire distally, becoming bracts. Racemes bracteate below or between proximalmost 1 or 2 flowers. Fruiting pedicels divaricate to divaricate-ascending, (straight), 2-10 mm. Flowers: calyx urceolate; sepals yellow or purplish, 5-7 mm, keeled, (apex recurved); petals pale yellow to whitish (with purple veins, recurved), 8-16 mm, blade 3-6 × 1.5-3.5 mm, margins not crisped, (undulate), claw 5-10 mm, narrower than blade; stamens in 3 unequal pairs; filaments (distinct): abaxial pair 2.5-6 mm, lateral pair 1.5-4 mm, adaxial pair 4-8 mm; anthers: abaxial and lateral pairs fertile, 3.5-4 mm, adaxial pair partially fertile, 1.5-2.3 mm; gynophore 0.5-1.5 mm. Fruits geniculately reflexed, smooth, straight, flattened, 3-9 cm × 1-1.5(-2.2) mm; valves each with obscure midvein; replum straight; ovules (22-)38-80 per ovary; style 0.2-1 mm; stigma obscurely 2-lobed. Seeds oblong, 1-1.5(-2.2) × 0.6-1 (-1.5) mm; wing (0-)0.05-0.1(-0.4) mm wide, distal. 2n = 28. Flowering Apr-Jul. Dry rock outcrops, granitic domes, adjacent road cuts, disturbed areas, open oak woodland; 200-1900 m; Calif. Streptanthus diversifolius is distributed in Butte, El Dorado, Fresno, Madera, Mariposa, Tuolumne, and Tulare counties.