Single-stemmed, fibrous-rooted perennial 3-10 dm; lower lvs long-petioled, the upper on short petioles dilated as far as the lfls; lfls lanceolate to rhombic or ovate, 4-15 cm, sharply and irregularly (often doubly) serrate or incised to sometimes lobed; rays 2-7, ascending, 1-5 cm; pedicels several, to 3 cm; fr dark, 5-8 mm; 2n=20. Woods, Que. and N.B. to Man., s. to Ga., Ala., and Tex.; Japan. June, July. (Deringa c.)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.