Description from Flora of China
Rhizome slender stoloniferous. Culms 50-100 cm tall, rather thick, triquetrous, densely hispidulous, dark red-brown and bladeless sheathed at base. Leaves longer than culm, 4-8 mm wide, flat, densely hirsute, rather long sheathed. Involucral bracts leaflike, longer than inflorescence, shortly sheathed, densely hirsute. Spikes 4 or 5, approximate; terminal spike male, linear-cylindric, 5-7 cm, nearly sessile; remaining spikes female, cylindric, 2.5-5 cm, densely many flowered, shortly pedunculate. Female glumes red-brown laterally, green at middle, ovate-lanceolate, 4-6 mm, membranous, laxly hirsute, 3-veined, apex acuminate, aristate. Utricles dark red-brown, obliquely patent, elliptic or broadly ovate, slightly inflated trigonous, 6-7 mm, thinly leathery, hirsute, distinctly several veined, base rounded, apex gradually narrowed to a medium-sized beak, orifice 2-toothed, teeth slightly long and strict. Nutlets elliptic or obovate, ca. 3 mm, apex mucronate; style base not thickened; stigmas 3. Fl. and fr. May-Jul.
● Wet places on mountain slopes, ditch sides, watersides; 1900-2900 m. Guizhou, Sichuan.