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.
Infrequent to rare in the northern counties in moist soil on the borders of marshes, bogs, and lakes; south of the lake area it is very rare, being restricted to a few rocky, wooded bluffs. The rays of the umbels and the principal veins of the under surface of the leaves of Indiana specimens are pubescent.