Phyllodia to 1 cm wide. Inflorescences racemes; pistillate pedicels 0.5--3 cm. 2n = 22.

Flowering summer--fall. Streams, lakes, and tidal areas; 0--700 m; N.B., Nfld. and Labr. (Nfld.), N.S., Ont., P.E.I., Que.; Ala., Ark., Conn., Del., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Nebr., N.H., N.J., N.Y., N.C., Ohio, Okla., Pa., R.I., S.C., S.Dak., Tenn., Tex., Vt., Va., Wash., W.Va., Wis.; West Indies (Cuba).

Infrequent in a part of the lake area and local southward. This species is usually found in shallow water or in very wet places about lakes, ponds, and artificial ponds and in ditches.