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.
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.