Description from Flora of China
Carex immanis C. B. Clarke; C. prescottiana Boott var. fargesii (Franchet) Kükenthal.
Rhizome indurate. Culms 45-95 cm tall, 3-5 mm thick, acutely trigonous, scabrous, clothed at base with dark reddish bladeless sheaths disintegrating into reticulate fibers. Leaves basal or cauline, longer or shorter than culm, blades broadly linear, 0.8-1.2 cm wide, flat, margins scabrous, revolute, apex acuminate. Lowest involucral bract leaflike, surpassing inflorescence, sheathless, remaining bracts setaceous. Spikes 5-8; terminal spike male, sometimes with a few female flowers at apex or in middle, linear, 65-80 × ca. 2 mm, with peduncle 2-3 mm; lateral spikes female, long cylindric, 50-90 × 5-6 mm, lowest peduncle 2-5 mm. Female glumes light reddish or light yellow pale, obovate, 1.8-2.7 mm, green 1-veined costa excurrent into a mucro at truncate or emarginate apex. Utricles light reddish, slightly longer than glume, ovate or lanceolate-oblong, 2.8-3 mm, membranous, faintly ferruginous glandular, conspicuously veined, beakless, emarginate at orifice. Nutlets castaneous, slightly loosely enveloped, ovate or obovate, plano-convex, ca. 2 mm; style base not thickened; stigmas 2. Fl. and fr. May-Jul.
● Shady places, streamsides; 900-2300 m. Guizhou, Hubei, Hunan, Sichuan.