Japan Flora: Slender, green or vivid green perennial with slender, elongate rhizomes; culms 50-80 cm. long, smooth, solitary or few; leaf-blades thin, flat, 10-15 cm. long, 1.2-3 mm. wide, often sparsely pilose above; sheaths slightly compressed, the lower sometimes puberulent; ligules 1-2 mm. long, truncate; panicles loose, open, green or yellowish green, 8-15 cm. long, 3-5 cm. wide, the branches subverticillate, slender, scabrous, spreading; spikelets 4-6 mm. long, prominently compressed, 3- or 5-flowered; glumes narrowly lanceolate, 2.5-3 mm. long, very acute, 3-nerved, scabrous on the keel; lemmas broadly lanceolate, about 3.5 mm. long, glabrous, with distinct intermediate nerves, the keel and marginal nerves pubescent on lower of the entire length, the web copious; anthers 1.2-1.5 mm. long.----- May-July. Mountain woods;
Honshu (centr. distr. and northw.), perhaps also in Hokkaido; rare. Korea.