Description from Flora of China
Rhizome thick and short, ligneous. Culms tufted, 30-60 cm tall, rather slender, triquetrous, smooth, leafy at base, purple-brown bladeless sheathed at lowermost part. Leaves slightly shorter than or nearly equaling culm, blades 4-6 mm wide, flat, rather soft, distinctly 2-veined laterally; sheaths rather long. Involucral bracts leaflike, longer than uppermost spike, rather long sheathed. Spikes 4 or 5, upper 3 or 4 contiguous at apex of culm, lowermost 1 or 2 rather remote; terminal spike male, linear, 1.5-3 cm, with short peduncle; lateral spikes 3-5, female, narrowly cylindric, 2-6 cm, rather loosely and biseriately many flowered, upper spikes subsessile, lower 1 or 2 with peduncles. Female glumes yellowish white, ovate, 1.5-1.8 mm, membranous, 1-veined, apex acute, muticous. Utricles brown-green, suberect, much longer than glume, ovate-elliptic, obtusely trigonous, 4-5 mm, membranous, glabrous, 5-7-veined, base rounded, apex gradually narrowed to a medium-sized beak, orifice emarginate to shortly 2-toothed. Nutlets brownish yellow, rather tightly enveloped, elliptic, trigonous, ca. 2 mm, base shortly stipitate, apex mucronate; style base not thickened; stigmas 3. Fl. and fr. Apr-May.
Roadsides, mountain slopes, watersides. Fujian, Guizhou, Hunan, Jiangsu, Jiangxi, Sichuan, Zhejiang [Japan, Korea].