Distribution: Occurring west of the Cascades crest and east in the Columbia River Gorge in Washington; southwestern British Columbia to California, east across the southern U.S. to the Atlantic Coast.
Habitat: Grassy balds, headlands, rocky outcroppings, and other to seasonally moist open areas at low elevations.
Growth Duration: Annual
Conservation Status: Not of concern
Slender, single-stemmed annual from a slender taproot, 0.5-6 dm. tall, with short, stiff, blunt bristles throughout.
Leaves 3-pinnate, long petiolate, the blades 3-10 cm. long and 1.5-7 cm. wide, the ultimate segments linear, 1-5 mm. long and 0.5-1 mm. wide.
Involucral bracts pinnatifid into linear segments up to 8 mm. long; bractlets of the involucel linear and entire, about equaling the pedicels; inflorescence 1-4 cm. wide, the rays up to 4 cm. long; ultimate umbellets with 5-12 white flowers.
Fruit oblong, 3-5 mm. long and 2 mm. wide, broadest below the middle, with prickles and bristles on the ribs.