1. Enemion biternatum Rafinesque, J. Phys. Chim. Hist. Nat. Arts. 91: 70. 1820.
Isopyrum biternatum (Rafinesque) Torrey & A. Gray
Stems 10-40 cm, weakly rhizomatous; roots fibrous. Leaves: leaflets irregularly 2-3-lobed, lobes sometimes with 1-3 secondary lobes, apex rounded, glandular-apiculate; surfaces abaxially glabrous. Inflorescences axillary, flowers solitary or loosely grouped in 2-4-flowered leafy racemes; peduncle not strongly clavate. Flowers: sepals 5.5-13.5 × 3.5-8.5 mm; stamens 25-50; filaments filiform to club-shaped, 1.8-5.8 mm. Follicles sessile, upright to widely divergent; body widely elliptic to widely obovate, 3.5-6.5 mm, gradually contracted into style beak; beak 1.7-3 mm. Seeds 2.1-2.7 mm, minutely pubescent. 2 n = 14.
Flowering spring. Moist deciduous woods of valleys, flood plains, and ravine bottoms, occasionally in open pastures, often on limey soils; 25-1000 m; Ont.; Ala., Ark., Fla., Ill., Ind., Iowa, Kans., Ky., Mich., Minn., Miss., Mo., N.Y., N.C., Ohio, Okla., S.C., S.Dak., Tenn., Va., W.Va., Wis.
Enemion biternatum has been mistaken for the superficially similar Thalictrum thalictroides because of its white flowers and compound Thalictrum -like leaves. Enemion biternatum is easily distinguished, however, by its few-seeded follicles and deeply lobed leaves with glandular-apiculate apices. Thalictrum thalictroides , on the other hand, is characterized by having achenes and somewhat crenate leaves with notched apices.