Japan Flora: Culms 5-40 cm. long, slender, tufted; leaves narrowly linear, 1-5 mm. wide, shorter chan to nearly as long as the culm; spikelets 2-6, erect, the terminal staminate, 4-20 mm. long, light green, the others pistillate, oblong to short-cyl indr ic, nearly sessile or the lower ones short-pedunculate, 5-30 mm. long, densely flowered, the lowest bracts leaflike, sheathing at base; pistillate scales ob­ovate, light green, acute or short-awned; perigynia slightly longer than the scales, obovoid, green, 1.5-3 mm. long, pubes­cent, many-nerved, abruptly short-beaked, minutely 2-toothed at tip; stigmas 3. Apr.-July. Abundant in open fields.

Hokkaido to Kyushu. Korea, China, India, and Australia.

var. puberula (Boott) T. Koyama. Plant low; leaves shorter than the culms; spikelets rather few-flowered, the lowest one often almost radi­cal.  Shady hillsides; Hokkaido, Honshu (centr. part and north.).

var. discoidea Boott. Plant slender, loosely tufted with long slender creeping rhizomes; spikelets small, crowded at the top of the culm; bracts barely sheathing; perigynia about 1.5 mm. long, less hairy. Hon­shu, Kyushu. Ryukyus.

var. fibrillosa (FY. & Sav.) Kuek. Plant robust; stolons tough, elongate; lowest bracks longer than the in­florescence; pistillate spikelets densely many-flowered; pistil­late scales easily falling off in fruit; perigynia about 3 mm. long, strongly ribbed, yellowish when mature. Sandy coasts; Honshu, Shikoku, Kyushu. s. Korea.