Acaulescent perennial herb, the lvs and peduncle arising from a long rhizome; petiole erect, to 5 dm; lvs ternate, each division pinnately 3-5-foliolate; lfls lance- elliptic to obovate, to 15 נ8 cm, acuminate, finely serrate, the lateral ones asymmetric at base; peduncles usually much shorter than the petioles, bearing (2)3(-7) umbels; styles distinct; fr nearly black; 2n=24. Woods; Nf. to D.C., Ind., Neb., and Colo., and in the mts. to Ga. May, June.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.