Herbs , 15-120 cm, mostly pubescent when young, often glabrate, having rhizomes, often with adventitious roots. Leaves 4-25 cm; petiole 1-10 cm; blade ovate, 2-17 × 1-10 cm, base cordate, apex acuminate. Racemes nodding to erect, fragrant, narrow, 5-35 cm. Floral bracts green, boat-shaped, 1.5-3 mm (distinct portion), adnate to pedicel. Schizocarps brown, 1.5-3 mm, rugose. Seed brown, 1-1.3 × 0.7-1 mm, smooth. 2 n = 22. Flowering spring-summer, sometimes early fall. Wet soil, fresh or slightly brackish water to depth of 5 dm; 0-500 m; Ont., Que.; Ala., Ark., Conn., Del., Fla., Ga., Ill., Ind., Kans., Ky., La., Md., Mich., Miss., Mo., N.J., N.Y., N.C., Ohio, Okla., Pa., R.I., S.C., Tenn., Tex., Va., W.Va. Some American Indians used Saururus cernuus for medicinal purposes (D. E. Moerman 1986).
Branched, 5-12 dm; lvs with long, basally sheathing petiole, the blade cordate-ovate, 6-15 cm; spikes 1 or 2, peduncled, terminal but often surpassed by axillary branches, 6-15 cm, nodding at the tip before anthesis; filaments white, 3-4 mm, much surpassing the pistils; fr 2-3 mm thick; 2n=22. Swamps and marshes; s. N. Engl. and s. Que. to Minn., s. to Fla. and Tex. June-Aug.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.