Nasturtium terrestre (Withering) W. T. Aiton var. occidentale S. Watson; Radicula pacifica (Howell) Greene; Rorippa hispida (Desvaux) Britton var. glabrata Lunell; R. islandica (Oeder ex Murray) Borbás subsp. fernaldiana (Butters & Abbe) Hultén; R. islandica var. fernaldiana Butters & Abbe; R. islandica var. glabra (O. E. Schulz) S. L. Welsh & Reveal; R. islandica var. glabrata (Lunell) Butters & Abbe; R. islandica var. occidentalis (S. Watson) Butters & Abbe; R. pacifica Howell; R. palustris subsp. fernaldiana (Butters & Abbe) Jonsell; R. palustris var. fernaldiana (Butters & Abbe) Stuckey; R. palustris subsp. glabra (O. E. Schulz) Stuckey; R. palustris var. glabra (O. E. Schulz) Roy L. Taylor & MacBryde; R. palustris var. glabrata (Lunell) Victorin; R. palustris subsp. occidentalis (S. Watson) Abrams; R. palustris var. occidentalis (S. Watson) Rollins; R. palustris var. pacifica (Howell) G. N. Jones; R. terrerstris (Withering) Fuss var. globosa A. Nelson

Stems usually glabrous, rarely sparsely pubescent proximally. Leaf blades: abaxial surface usually glabrous, rarely sparsely pubescent proximally. 2n = 32.

Flowering Mar-Sep. Marshlands, pastures, prairies, meadows, swales, flats, sand bars, wet grounds, stream banks, moist depressions, ditches, estuaries, waste grounds, roadsides, sloughs, shores of lakes and ponds, bogs, thickets, grasslands; 0-3200[-4000] m; Alta., B.C., Man., Nfld. and Labr., N.W.T., N.S., Ont., P.E.I., Que., Sask., Yukon; Ala., Alaska, Ariz., Ark., Calif., Colo., Conn., Del., D.C., Fla., Ga., Idaho, Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Mont., Nebr., Nev., N.H., N.J., N.Mex., N.Y., N.C., N.Dak., Ohio, Okla., Oreg., Pa., R.I., S.C., S.Dak., Tenn., Tex., Utah, Vt., Va., Wash., W.Va., Wis., Wyo.; Europe; Asia; introduced in n Mexico, South America, Australia.