Japan Flora: Culms 1-1.5 m. long, stout, terete, with 5-7 distant nodes; radical leaves shorter than the culm, the cauline 4-8 mm. wide, elongate, long-attenuate, the sheath 3-10 cm. long, tightly surrounding the culm; inflorescence of 2-5 interrupted subcompound panicles, the terminal one largest, 5-10 cm. long, the subtending bracts several, 2 or 3 of them longer than the others, longer than the inflorescence; spikelets sessile, densely congested in globular-capitate clusters of 10-20, ovate- oblong, 4-6 mm. long, dark brownish gray; scales lanceolate, 3 mm. long, 0.7 mm. wide, acute; achenes obovate, com­pressed-trigonous, 1 mm. long, mucronate, pale, the bristles 5-6, about 5 mm. long, sparsely ascending-spinulose at tip.  Aug.-Oct. Swamps in low grounds.

Honshu, Shikoku, Kyushu.