Stems erect, leafy, slender, (20-)30-100(-120) cm, glabrous. Leaves mostly cauline, proximal leaves petiolate, distalmost sessile. Leaf blade (2-)3-ternate; leaflets obovate to orbiculate or cordate, usually 3-cleft and divisions 3-lobed, thin, 10-20 mm, surfaces abaxially often glandular-puberulent. Inflorescences axillary, 1-few flowers, diffuse, leafy; bracts leaflike, large. Flowers: pedicels abruptly recurved in fruit; sepals whitish or greenish, often purplish tinged, elliptic, 2-3.5(-4) mm; stamens 12-20, whitish; filaments 3-4.5 mm; anthers 0.5-0.8 mm. Achenes (4-)6-12; stipe 0.3-1.5 mm; body obliquely obovate to half-rhombic, strongly compressed, (4-)5-6 × 3-4 mm, abaxial margin straight, glabrous or glandular-puberulent, faintly 3-4(-5)-veined; beak 1-1.5 mm. Flowering late spring-summer (Jun-Aug). Meadows, damp thickets, bogs, and coniferous, deciduous, and riparian woods; 0-3000 m; Alta., B.C., Man., N.W.T., Ont., Sask., Yukon; Alaska, Calif., Colo., Idaho, Mont., Nev., Oreg., Utah, Wyo.; ne Asia. The Cheyenne the flowers and ground plants of Thalictrum sparsiflorum medicinally to make their horses 'spirited, long-winded, and enduring' (D. E. Moerman 1986).