Description from Flora of China
Carex pisanensis T. Koyama.
Rhizome obliquely ascending, ligneous, several branched. Culms densely tufted, 10-30 cm tall, ca. 1 mm thick, slender, obtusely trigonous, smooth. Leaves shorter than culm, flat, blades 1-1.5 mm wide, soft, dark brown and persistent sheathed at base; basal sheaths eventually disintegrating into fibers. Involucral bracts spathelike, involucral bract sheaths long, green, white hyaline on margins, lowermost one with short involucral bract leaf, upper ones setaceous. Spikes 3 or 4; terminal spike male, oblong, 8-10 mm, taller than adjacent female spike, densely few flowered; lateral spikes 2 or 3, female, lowermost one sometimes basal, uppermost one near male spike, others remote, cylindric, 1-2.5 cm, ca. 3 mm thick, densely many flowered. Female glumes brown or purple-brown, oblong, 3-3.5 mm, papery, green 1-veined, apex obtuse, mucronate. Utricles yellow-brown or greenish, equaling glume, obovate, trigonous, 3-3.2 mm, densely pubescent, 2-veined laterally, not distinctly thinly veined, base contracted into a short stipe, apex abruptly contracted into a short beak, orifice obliquely truncate. Nutlets brown at maturity, obovate, trigonous, ca. 2.2 mm, base subsessile, apex shortly beaked; style base not thickened; stigmas 3. Fl. and fr. Jun-Sep.
Meadow thickets on high mountains, forest margins or grasslands at riversides; 2000-4300 m. SW and W Sichuan, E Xizang, NW Yunnan [Bhutan, NE India, Nepal].