Distribution: Occurring chiefly east of the Cascades crest in Washington; southern British Columbia to California, east to Montana and Nevada.
Habitat: Dry, open areas in sagebrush, grasslands, and ponderosa pine forest openings.
Conservation Status: Not of concern
Slender, widely-branched annual, up to 1 dm. tall, occasionally taller, somewhat fine-hairy and glandular.
Leaves linear or linear-oblong, 1-2 cm long and 1-2.5 mm. wide, all opposite.
Heads in the forks of the stem and in small terminal clusters; involucre of 5 or fewer bracts, 2-4 mm. high, bearing tack-shaped, sticky glands; ray flowers minute, their achenes compressed at right angles to a radius through the head and enclosed by the involucral bracts; disk flowers usually solitary, yellow, and enclosed by the united bracts of the receptacle.
Achenes somewhat compressed at right angles to a radius of the head.