Description from Flora of China
Rhizome short. Culms densely tufted, 10-30 cm tall, not up to 1.5 mm thick, compressed triquetrous, smooth. Leaves rather shorter than culm, scabrous and involute on margins, linear, slightly stiff, blades 0.8-1 mm wide, dark brown and persistent sheathed at base, sheaths eventually disintegrating into fibers. Involucral bracts spathelike, sheaths green abaxially and purple-red adaxially, white hyaline on margins, lowermost one with setaceous involucral bract leaf, upper ones without leaf. Spikes 2-4, lowermost spike remote, others approximate; terminal spike male, taller than adjacent female spike, cylindric, 8-10 mm, densely many flowered; lateral spikes 1-3, female, subcylindric, 7-20 mm, densely 4-10- or more flowered; peduncles short, usually not exserted or slightly exserted from involucral bract sheath. Female glumes purple-brown laterally, green at middle, oblong, 4.5-5 mm, papery, 3-veined, margins broadly white hyaline, apex acute, shortly awned. Utricle slightly shorter than glume, obovate-oblong, obtusely trigonous, 3.5-4 mm, papery, densely pubescent, 2-veined laterally and thinly several veined, base gradually narrowed to a short stipe, apex contracted into a recurved and short beak or nearly beakless, orifice truncate. Nutlets brown at maturity, obovate-elliptic, obtusely trigonous, 3-3.2 mm, slightly concave on 3 faces, base shortly stipitate or nearly estipitate, apex with recurved and short beak; style rather short, base not thickened; stigmas 3. Fl. and fr. Apr-Aug.
● Sunny meadow thickets on high mountains; 1700-3900 m. Gansu, S Qinghai, SW and W Sichuan, E and S Xizang, NW Yunnan.