糙芒薹草 cao mang tai cao

Rhizome creeping. Culms 40-90 cm tall, acutely trigonous, smooth, scabrous above, clothed at base with dark purple-red or brown bladeless sheaths. Leaves shorter or slightly longer than culm, blades linear, 4-6 mm wide, flat, margins revolute, scabrous, apex acuminate. Involucral bracts leaflike, equaling or slightly longer than inflorescence, sheathless. Spikes 4-7, subfasciculate, narrowly cylindric, 5-6 cm; upper 1-4 spikes male, sometimes androgynous; remaining spikes usually female, sometimes upper spikes male, lower female, lowest spike with peduncle up to ca. 1 cm. Female glumes dark purple-black, ovate or oblong-lanceolate, ca. 3 mm, green 3-veined costa excurrent into a scabrous awn at entire or emarginate apex. Utricles yellow-brown, ± equaling glume, elliptic, ca. 3 mm, glabrous, veined, apex abruptly contracted into a conic short beak, orifice entire or emarginate. Nutlets laxly enveloped, ovoid, ca. 2 mm; stigmas 2. Fl. and fr. Jun.

Moist places in forests; ca. 3100 m. Xizang [Bhutan, India, Nepal].