Herbs, to 1 m. Leaves emersed, petiolate; blade linear-lanceolate to broadly elliptic or oval, to 35 × 3–12 cm. Inflorescences to 1 m. Flowers chasmogamous; sepals 3–6 mm; petals white, 3.5–6 mm, margins erose, apex obtuse; anthers ovoid, 0.6–1 mm; style curved, 0.4–0.6 mm, equal to ovary length. Fruiting heads 4.1–7 mm diam; achenes ovoid, 2.1–3 mm, abaxial keel broadly rounded with 1 median abaxial groove, beak erect or nearly erect. 2n = 28.

Phenology: Flowering spring–fall.
Habitat: Shallow muddy ponds, stream margins, marshes, and ditches
Elevation: 0–2000 m

Distribution

• Generated Map
• Legacy Map

Alta., B.C., Man., N.B., Nfld. and Labr., N.W.T., N.S., Ont., P.E.I., Que., Sask., Alaska, Ariz., Calif., Colo., Conn., Idaho, Ill., Ind., Iowa, Kans., Maine, Mass., Mich., Minn., Mont., Nebr., Nev., N.H., N.Mex., N.Y., N.Dak., Ohio, Okla., Oreg., Pa., R.I., S.Dak., Utah, Vt., Wash., Wis., Wyo., n Mexico

Discussion

I have seen no specimens from West Virginia, but although the species is to be expected there.

Selected References

None.

Lower Taxa

None.

"equal" is not a number.