扁茎薹草 bian jing tai cao

Rhizome short. Culms densely tufted, 1 or 2 borne in a leaf axil, 8-18 cm tall, ca. 1 mm thick, compressed, soft and smooth. Leaves 2 × as long as culm or more, flat, 3.5-7 mm wide, soft, glabrous, scabrous on margins, with brown persistent sheaths. Involucral bracts sheathlike, blade scalelike. Spikes usually 1 or 2, androgynous, remote, cylindric, 5-10 mm, 2-3 mm thick; male part of spike 2 × as long as female part or more (rarely both parts equal), densely many flowered; female part few flowered; lateral spike usually borne from upper part of culm, peduncle short and compressed. Female glumes yellowish, broadly ovate or oblong, 1.5-2 mm, papery, green 1-costate and thinly few veined, margins narrowly membranous, apex obtuse. Utricles pale green, ovate-elliptic, compressed trigonous, 2-3 mm, papery, loosely pubescent on upper part, later glabrescent, 2-veined laterally and thinly few veined, base subrounded, margins ciliate, apex attenuate into an indistinct beak, orifice obliquely truncate. Nutlets dark brown at maturity, elliptic, trigonous, sides slightly concave, ca. 2 mm, base cuneate, nearly estipitate, apex attenuate, with a secund and short beak; style cylindric, brown granular-punctate, base slightly thickened; stigmas 3. Fl. and fr. Sep-Dec.

● On rocky mountain slopes in forests or grasslands at riversides; 1600-2800 m. Hainan (Wuzhi Shan).