Distribution: Occurring west of the Cascades crest and in the northeastern corner of Washington; Alaska to Oregon, east to the Rocky Mountains, northern Great Plains, and Great Lakes region.
Habitat: Swamps and other wet places from along the coast to middle elevations in the mountains.
Conservation Status: Not of concern
Herbaceous perennial from extensive creeping rhizomes, the culms stout, 3-7 dm. tall.
Leaves few, mostly basal, with well-developed sheath and narrow, channeled blade up to 2 mm. wide; sheathes closed; uppermost sheath about mid-culm, often bladeless.
Spikelet terminal and solitary, with up to 7 sterile scales, the outermost enlarged, up to 2 cm. long; fertile scales subtending the flowers partly blackish-green, with the tip and margins paler, russet-flecked on a whitish background; perianth consisting of numerous capillary bristles 2-4 cm. long, reddish to white; stamens 3; style trifid.
Achenes dark, about 2 mm. long, obovate.