Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across most of North America to the Atlantic Coast.

Habitat: Sloughs and slow-moving fresh water.

Flowers: June-August

Origin: Native

Growth Duration: Perennial

Conservation Status: Not of concern

Pollination: Wind

Small aquatic herbs, the stems 5-20 cm. long, submerged or partially floating; leaf bases joined by small, winged ridges.

Submerged leaves linear, 5-20 mm. long, thin, 1-nerved, with a slight notch at the tip; floating and emergent leaves broadly spatulate, up to 4 mm. broad, 3-nerved.

Flowers imperfect, sessile in the leaf axils, each consisting of a single pistil or 1 stamen or both; styles 2, distinct, 1-2.5 mm. long, deciduous; floral bracts present.

Carpels 2, oblong-obovate, about 1 mm. long and 0.7 mm. broad, with pit-like markings in vertical lines.