Early Meadow Rue

Glandular plants of Thalictrum dioicum have often been misidentified as T . revolutum despite important differences, especially the leaflets having crenate versus entire lobe margins, respectively. The stamens in both T . dioicum and T . revolutum are pendulous.

Native Americans used roots of Thalictrum dioicum in various preparations to treat diarrhea and vomiting and for heart palpitations (D. E. Moerman 1986).

Roots yellow to light brown, fibrous, from stout caudex. Stems erect, 30-80 cm, glabrous or glandular. Leaves basal and cauline, petiolate. Leaf blade 1-4×-ternately compound; leaflets reniform or cordate to obovate or orbiculate, apically 3-12-lobed, 10-45 mm wide, lobe margins often crenate, surfaces abaxially glabrous or glandular. Inflorescences terminal and axillary, panicles to corymbs, many flowered. Flowers: sepals greenish to purple, ovate or obovate to oval, 1.8-4 mm; filaments yellow to greenish yellow, 3.5-5.5 mm; anthers 2-4 mm, mucronate to acuminate; stigma purple. Achenes (3-)7--13, not reflexed, sessile or nearly so; stipe terete, 0-0.2 mm; body ovoid to ellipsoid, not laterally compressed, 3.5-5 mm, glabrous, very strongly veined, veins not anastomosing-reticulate; beak 1.5-3 mm.

Man., Ont., Que.; Ala., Conn., D.C., Ga., Ill., Ind., Iowa, Kans., Ky., Maine, Md., Mass., Mich., Minn., Mo., Nebr., N.H., N.J., N.Y., N.C., N.Dak., Ohio, Pa., R.I., S.C., S.Dak., Tenn., Vt., Va., W.Va., Wis.

Flowering spring (Apr-Jun).

Rocky woods, ravines, and alluvial terraces, mountains and piedmont; 10-1000m.