溪水薹草 xi shui tai cao

Rhizome short. Culms densely tufted, 40-90 cm tall, trigonous, scabrous, clothed at base with yellow-brown, slightly lustrous, bladeless sheaths disintegrating into reticulate fibers. Leaves equaling or slightly longer than culm, blades green, linear, 2.5-4 mm wide, flat, margins revolute. Involucral bracts leaflike, shorter than inflorescence, sheathless. Spikes 3-5; terminal spike male, linear, 3-4 cm, with peduncle; lateral spikes female, narrowly cylindric, 1.5-5 cm, densely many flowered, sometimes slightly laxly flowered at base, lower spikes with short peduncles, others sessile. Female glumes dark ferruginous or purple-brown, lanceolate or oblong, ca. 3 mm, green 3-veined costa forming a scabrous mucro. Utricles yellow-green, longer than glume, obovate or ovate, compressed biconvex, 3-4 mm, hardly veined, sometimes finely few veined, base truncate, upper margins scabrous, apical beak deeply 2-lobed at orifice. Nutlets tightly enveloped, ovoid or broadly obovoid, sub-biconvex, 2-2.5 mm, base broadly truncate; style base not thickened; stigmas 2. Fl. and fr. Jul-Aug.

Forests, streamsides, moist places; 700-900 m. Anhui, Hebei, Jilin, Liaoning, Shaanxi [Japan, Korea, Russia (Far East)].