Distribution: Known from Klickitat County in Washington; Washington south to California.
Habitat: Dry, open areas at low elevation.
Conservation Status: Not of concern
Slender annual, the spreading to erect stems 1-4 dm. long, simple to freely-branched, mostly glabrous below, puberulent to pubescent above and throughout the inflorescence.
Leaves alternate, deeply pinnatified into 3-7 pairs of linear segments, the basal ones 3-10 cm. long, the cauline leaves gradually reduced, the upper ones sometimes entire.
Inflorescence of bractless, open and elongate racemes; pedicles strongly flattened, ascending; sepals 4, 1-1.5 mm. long; petals 4, white, 1-2 mm. long; stamens usually 6; style lacking.
Silicles ovate to oblong-obicular, 3.5-4.5 mm. long, glabrous, lightly veined, both surfaces smooth and shining, the slightly winged margins upturned all the way around, the tip slightly notched.