Perennials. Culms tufted, 10-60 cm tall, 1-1.5 mm thick, flat or compressed triquetrous, longitudinally sulcate, very laxly puberulent. Leaves basal; sheath tubular, 1.8-2.5 cm, glabrous, basal ones without a blade, apical ones with a blade; leaf blade linear, ca. 1/2 as long as culm, 2-4 mm wide, papery, margin revolute, apex acuminate. Involucral bracts 2 or 3, leaflike, 2-7 cm, not sheathing. Spikes (3 or)4-7-fascicled, ovoid to broadly ovoid, 5-10 × ca. 5.5 mm, with numerous bractlets and spikelets; bractlets pale and purple striate, oblanceolate, ca. 2 mm, keeled, submembranous, apex subtruncate to acuminate. Spikelets with 2 glumes and 1 bisexual flower; basal glume elliptic, ca. 1.5 mm, membranous, 5-veined, margin involute, apex obtuse; apical glume ovate-lanceolate, ca. 1.5 mm, with a bisexual flower, apex acute. Stamens 2; anthers narrowly oblong. Style of medium length; stigmas 3, nearly as long as style, puberulent. Nutlet brown when mature, oblong-obovoid, ca. 1 mm, biconvex, with punctate processes on surface, apex rounded and shortly apiculate. Fl. and fr. May-Oct. 2n = 26.