Japan Flora: Rhizomes very short or nearly absent; culms 10-50 cm. long, slightly compressed, surrounded below by a bladeless sheath; leaves flat, 1.5-3 mm. wide; inflorescence simple or subcompound; the bracts 4-6, erect, 1-2 cm. long; spikelets many, ovoid, 4-6 mm. long, 2.5-3 mm. thick, dark brown to reddish brown; scales membranous, narrowly ovate, about 2 mm. long, obtuse; achenes biconvex, lustrous, stramineous, obovate, 0.8 mm. long, with distinct, transversely oblong reticulations; stamens 1 or 2, the anthers linear, 0.5 mm. long. Aug.-Oct
Honshu (Shimotsuke, Noto and westw., including Sado Isl.)> Shikoku, Kyushu. Korea, Ryukyus, and China.