Distribution: Occurring west of the Cascades crest in Washington; Alaska to Washington, east across the northern U.S. and Canada to the Atlantic Coast.

Habitat: Lakes, slow streams, and alkaline water.

Flowers: June-August

Origin: Native

Growth Duration: Perennial

Conservation Status: Sensitive in Washington (WANHP)

Pollination: Wind

Annual, perennial herb, slender, rhizomes absent; cauline stems slightly compressed, 35-90 cm, without spots; glands yellow-green to gold, 0.2-1 mm diameter; turions terminal, abundant, 3.5-7.8 cm x 2.3--5.1 mm, soft.

Leaves 2-ranked; outer leaves 3-4 per side, base not corrugate, apex apiculate to obtuse; inner leaves undifferentiated; leaves submersed, often spirally arranged, sessile, flaccid; stipules persistent, inconspicuous, convolute, free from blade, not ligulate, white, 0.6-1.8 cm, fibrous, rarely shredding at tip, apex obtuse; blade light green to somewhat reddish, linear, not arcuate, 3-8.2 cm x 1--3.5 mm, base slightly tapering, without basal lobes, not clasping, margins entire, not crispate, apex not hoodlike, obtuse or round-apiculate, lacunae in 1-3 rows each side of midrib; veins 3.

Inflorescences panicle of spikes, unbranched, emersed, cylindric; peduncles not dimorphic, axillary, erect, rarely recurved, cylindric, 0.8-1.9(-4.2) cm, may project above water surface; spike not dimorphic, cylindric, 8-13 mm; pistils 1 or 4

Fruits sessile, olive-green to brown, obovoid, turgid, abaxially keeled or not, laterally keeled or not, 2.5--3.6 x 1.7--2.4 mm, lateral keels without points; beak erect, 0.8-1 mm; sides without basal tubercles; embryo with 1 full spiral.