Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to California, east across North America to the Atlantic Coast
Habitat: Wet meadows, shorelines, and disturbed open areas where moist.
Conservation Status: Not of concern
Monoecious, coarse annual with alternate leaves, 1-5 dm. tall
Leaves broadly ovate to sub-orbicular, generally cordate or deltoid at the base, with long petioles and without spines.
Staminate heads uppermost, many-flowered; involucre of separate bracts; receptacle cylindric, chaffy; involucre of the pistillate heads completely enclosing the 2 flowers, forming a 2-chambered bur with hooked prickles; pappus none.
Achenes thick, solitary in the chambers of the bur.