Japan Flora: Culms 40-100 cm. long, decumbent at base, rather slender, often retrorsely scabrous below the panicle; leaf­blades green, flat, soft, 10-20 cm. long, 3-5 mm. wide; sheaths slightly compressed, often somewhat retrorsely scabrous; ligules hyaline, deltoid, 3-6 mm. long; panicles ovate, open, 10-20 cm. long, the branches subverticillate, scabrous; spikelets green, 2.5-35 mm. long, 2- or 3-flowered; glumes lanceolate, about 2.5 mm. long, acute, the lower 1- to 3-nerved, the upper 3-nerved; lemmas 2.5-3 mm. long, narrowly ovate, acute, 3-nerved, glabrous on the sides, the keel and marginal nerves short-pubescent near base, the web elongate; anthers 1.2-1.7 mm. long.  May-June. Lowlands, possibly naturalized. 

Hokkaido, Honshu (centr. distr. and northw.). Europe and w. Asia.