Japan Flora: Rhi­zomes long-creeping; culms distant, 10-30 cm. long, scabrous; leaf-blades, 2-3 mm. wide, greenish; spikes several, androgy­nous, oval, 5-8 mm. long, densely aggregated into a narrow, ovate, bractless head; pistillate scales narrowly ovate, ferru- gineous-castaneous, acuminate; perigynia slightly longer than the subtending scales, ovoid, 3-4 mm. long, spreading, plano­convex, crescent-shaped in transverse section, faintly nerved, tightly inclosing the achene, margins acute, spongy-thickened at base, the long beak scabrous-margined, the tip membranous. May-June. Sandy grassy places in lowlands.

Hokkaido, Honshu, Kyushu; common. Korea, Ussuri, Sakhalin, and Kuriles.