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

Habitat: Marshes, muddy shores, and other wet places.

Flowers: June-September

Origin: Native

Growth Duration: Annual, Perennial

Conservation Status: Not of concern

Pollination: Wind

Very slender perennial from slender, branching rhizomes, forming dense tufts; culms filiform, 3-12 cm. tall, the basal sheaths pale or purplish.

Leaves all basal and reduced to sheaths.

Spikelet solitary and terminal, 2.5-7 mm. long, 3- to 15-flowered; scales of the spikelets spirally arranged, 1.5-2.2 mm. long, translucent, with a greenish midrib and paler margins; perianth of 3-4 bristles, equaling the achene, or wanting; stamens 3; style trifid, thickened at the base.

Achenes white to pale gray, 0.7-1.1 mm. long, with a conic tubercle (the thickened base of the style), the body obovoid, longitudinally 8- to 18-ribbed.