Perennial, woody below, with slender stems 1-3 m, usually arched and rooting at the tip; lvs opposite or more often in whorls of 3 or 4, short-petiolate, lanceolate, 5-16 × 2-5 cm; fls in dense cymes in the upper axils, the narrow pet pink-purple, 10-15 mm; fr 5 mm thick; 2n=32. Swamps and still water-courses. July-Sept. Var. verticillatus, with the pedicels and lower lf-surface ±tomentulose, occurs mostly near the coast from Me. to Fla. and La., and in the Mississippi Valley to Ind. and Mo. Var. laevigatus Torr. & A. Gray, with glabrous pedicels and lvs, is mostly inland, from N.S. and Que. to Minn., s. to e. Tenn.

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

In the mucky or peaty borders of lakes, bogs, and swamps. Infrequent in the lake area, and very rare southward. [Variety laevigatus has glabrous stems and lower leaf surfaces. It grows] on the mucky or peaty borders of lakes, bogs, and swamps. Rather rare and not so frequent as the pubescent form.

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Indiana Coefficient of Conservatism: C = 8

Wetland Indicator Status: OBL