Schoenus albus Linnaeus, Sp. Pl. 1: 44. 1753.

Perennials. Rhizomes short, slender. Culms tufted, erect, 15-42(-50) cm tall, 0.5-0.8 mm thick, apically slightly scabrous. Leaves shorter than culm; sheath straw-colored brown, basal ones with a blade or bladeless; leaf blade filiform, 0.7-2 mm wide, papery, margin involute. Involucral bracts leaflike, basal ones with a sheath, apical ones sheathless. Inflorescences paniculate, consisting of terminal and lateral subcapitate anthelae. Spikelets fascicled in a group of 2-7, sessile or shortly pedunculate, narrowly ovoid, 5-6 mm, 2-flowered. Glumes 5 or 6, at first white turning pale brown, ovate to ovate-lanceolate, membranous, keeled, apex mucronate. Perianth bristles 9-13, longer than nutlet, retrorsely scabrous, base sparsely hispid. Stamens 2; filaments as long as nutlet and style base; anthers linear. Style filiform, base dilated; stigmas 2, almost as long as style. Nutlet yellowish green to greenish brown, obovoid to oblong-obovoid, 1.5-2.5 mm, biconvex, ± smooth to obscurely wrinkled; persistent style base conic-subulate, 1/2-2/3 as long as nutlet. Fl. and fr. Aug. 2n = 26.

Swamps, wet places; ca. 900 m. Jilin, Taiwan [Japan, Kazakhstan, Korea, Russia; SW Asia, Caribbean (Puerto Rico), Europe, North America].