Distribution: Alaska east to Newfoundland, south to California and New Mexico.
Habitat: Swamps, wet meadows, and stream margins, often growing in 1-3 feet of water.
Flowers: May - October
Conservation Status: Not of concern
Strongly rhizomatous perennial, the culms erect to decumbent and freely rooting, up to 1 m. tall.
Sheaths open for 1-4 cm., flattened, glabrous; ligules 5-10 mm. long, entire but often splitting; blades flat or folded, 3-5 mm. broad.
Inflorescence a narrow panicle up to 4.5 dm. long, the branches ascending; spikelets 6- to 11-flowered, linear, terete, 10-12 mm. long; glumes papery, 1-nerved, the first 2-2.5 mm. long, the second slightly longer; lemmas 3-4 mm. long, prominently 7-nerved to the scarious upper margin, the nerves non-convergent; stamens 3.