Distribution: Occurring chiefly east of the Cascades crest and along the Columbia River in Washington; Washington to California, east across most of North America to the Atlantic Coast.

Habitat: Wet places, along the banks of large streams, in the valleys and lowlands.

Flowers: July-September

Origin: Native

Growth Duration: Perennial

Conservation Status: Not of concern

Pollination: Wind

Short-lived perennial without rhizomes, the sharply triangular, solitary or few solid stems 1-6 dm. tall.

Leaves several, grass-like, crowded at the base, 2-10 mm. wide, the sheaths closed.

Spikelets numerous, in short, cylindric spikes, spreading at right angles from the elongate rachis, 6-25 mm. long and 1-2 mm. wide; scales of the spikelets in two vertical rows, several nerved; axis of the spikelets with translucent wings that clasp the lower part of each achene; stamens 3; style trifid.

Achenes unequally triangular, 1.5-2 mm. long, 3-4 times as long as wide.