Roots black, tuberous. Stems erect, scapose, 10-30 cm, glabrous. Leaves basal; petiole 10-30 cm. Leaf blade 2×-ternately compound; leaflets widely ovate or obovate to nearly rotund, apically 3-lobed, 8-30 mm wide, surfaces glabrous. Inflorescences umbels or flowers solitary, (1-)3-6-flowered; involucral bracts usually 3-foliolate, petiolate and opposite, or sessile with leaflets appearing to be whorls of 6 petiolate leaves, otherwise similar to basal leaves. Flowers: sepals not caducous, white to pinkish, showy, elliptic to obovate, 5-18 mm, longer than stamens; filaments narrowly clavate, 3-4 mm; anthers 0.4-0.7 mm. Achenes (4-)8-12(-15), short-stipitate; stipe 0.1-0.4 mm; body ovoid to fusiform, 3-4.5 mm, prominently 8-10-veined. Flowering spring (Mar-Jun). Deciduous woods, banks, and thickets; 0-300 m; Ont.; Ala., Ark., Conn., Del., D.C., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., La., Maine, Mass., Mich., Minn., Miss., Mo., N.H., N.J., N.Y., N.C., Ohio, Okla., Pa., R.I., S.C., Tenn., Vt., Va., W.Va., Wis. In Thalictrum , T . thalictroides is unique in having umbelliform inflorescences and is therefore easy to identify. Based on this one distinction, many botanists still place it in the genus Anemonella . The leaflets, flowers, and fruits, however, are not unlike those of Thalictrum . The Cherokee used infusions prepared from the roots of Thalictrum thalictroides to treat diarrhea and vomiting (D. E. Moerman 1986).
From Flora of Indiana (1940) by Charles C. Deam
Infrequent to very frequent in all parts of the state except in the prairie areas and in very sandy areas. This is strictly a woodland plant which is found generally in dry soil, usually on slopes and banks along streams and ravines. This species is variable in many ways and some of the variations have received names. Hill (Bot. Gaz. 10: 262. 1885.) wrote of finding specimens near Hobart, Lake County, with "flowers greatly doubled, of 20-30 purplish petals, alternating in whorls."