Description from Flora of China
Scirpus comosus Wallich in Roxburgh, Fl. Ind. 1: 234. 1820; Erioscirpus comosus (Wallich) Palla.
Rhizomes short, stout. Culms densely tufted, obtusely 3-angled or rarely cylindric, 14-78 cm tall, 1-2 mm thick, smooth, clothed at base with black to brown leaf sheaths. Leaves many, overtopping inflorescence; leaf blade linear, 0.5-1 mm wide, margin involute and scabrous, gradually tapering and setaceous toward apex. Involucral bracts leaflike, overtopping inflorescence; bractlets lanceolate, margin scabrous, apically setaceous. Inflorescence a large compound or decompound anthela, 6-22 cm. Spikelets many, solitary or a cluster of 2 or 3, oblong but ellipsoid at anthesis, 6-12 mm. Glumes brown, ovate-lanceolate, 2.3-3 mm, membranous, keel green, excurrent into a mucro at acute to obtuse apex; basal 4 glumes empty. Perianth bristles many, surpassing glume at maturity, ca. 7 mm, smooth. Stamens 2; anthers purplish black, narrowly ovoid, apex mucronate. Style shorter than nutlet; stigmas 3. Nutlet narrowly oblong, ca. 2.5 × 0.5 mm (including beak), compressed 3-sided. Fl. and fr. May-Nov. 2n = 52.
Crevices on rock or cliffs, grassland slopes; 500-2800 m. Chongqing, S Gansu, Guangxi, Guizhou, Hubei, NW Hunan, Sichuan, SE Xizang, Yunnan [Afghanistan, Bangladesh, Bhutan, N India, Indonesia (Java), Kashmir, N Myanmar, Nepal, Pakistan, Vietnam; SW Asia].