Stout, to 2 m, glabrous or nearly so to the infl; lower lvs 1-3 dm, long-petiolate, the upper progressively reduced, with broad, sheathing petioles; lfls ovate to lanceolate, 4-10 cm, acute, sharply serrate, thinly margined and only rarely ciliate, glabrous or minutely hairy beneath; umbels 1-2 dm wide, with 20-45 thinly hairy rays; fr oblong-elliptic, 4-6.5 mm, rounded at base, glabrous, the lateral wings thin, flat, broad; oil-tubes numerous; seed loose in the pericarp; 2n=22. Swamps and wet woods; Lab. to Minn., s. to Del., W.Va., and Ind. June-Aug.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
©The New York Botanical Garden. All rights reserved. Used by permission.
From Flora of Indiana (1940) by Charles C. Deam
Infrequent in the northern two thirds of the state, being more frequent in the northern counties. In marshes, in mucky soil about lakes and ponds, and in alluvial bottoms along streams.