Distribution: East of the Cascades in Klickitat County, Washington, and Oregon, south to northern California.
Habitat: Moist meadows and vernal pools, and other moist, open places in the foothills and lowlands.
Flowers: May - July
Growth Duration: Annual
Conservation Status: Not of concern
Low annual up to 1 dm. tall, usually branched from the base, puberulent.
Leaves few, rather soft, pinnatifid, pale green, up to 3.5 cm. long, the rachis up to 2 mm. wide, the lateral segments few and small, the terminal one elongate, entire or with spiny teeth.
Inflorescence of dense, leafy-bracteate, sub-glabrous heads terminating the stem and branches, the bracts shorter and more dissected than the leaves; calyx 5-6 mm. long, with broad, translucent intervals between the ribs, white-hairy in the mouth, the 5 lobes unequal, often trifid; corolla white, 4-6 mm. long, the 5 lobes oblong, 1 mm. long, with a single mid-vein; filaments inserted about 0.4 mm. below the sinuses of the corolla; stigmas 2, very small, united; ovary 2-celled, superior.