米柱薹草 mi zhu tai cao

Rhizome stoloniferous, stolons slender. Culms loosely tufted, 30-70 cm tall, acutely triquetrous, smooth on lower part, scabrous on angles of upper part, purple-brown and bladeless sheathed at base, sheaths disintegrating into reticulate fibers. Leaves slightly shorter than culm, blades 2-3 mm wide, flat or conduplicate at lower part, slightly revolute when dry, slightly stiff, red-brown and rather long sheathed. Involucral bracts leaflike, linear, slightly shorter than inflorescence, not sheathed. Spikes 3 or 4, rather remote; uppermost 1 or 2 spikes male, narrowly oblong or lanceolate, (1-)2-3 cm, subsessile; female spikes 2 or 3, oblong or ovoid, 0.8-2 cm, densely many flowered, lowermost one very shortly pedunculate, others sessile. Female glumes dark red-brown laterally, brownish at middle, ovate or oblong-ovate, ca. 3 mm, membranous, 1-veined, apex acute or acuminate, sometimes mucronate. Utricles greenish brown, obliquely patent, equaling or slightly longer than glume, elliptic or subovate, slightly inflated trigonous, 2.5-3 mm, subleathery, glabrous, papillose, distinctly several veined, base abruptly contracted into a short stipe, apex abruptly narrowed into a short beak, orifice emarginate, slightly purple-brown. Nutlets stramineous, subloosely enveloped, broadly obovate, trigonous, ca. 2 mm, base broadly truncate, apex mucronate; style base thickened; stigmas 3. Fl. and fr. May-Jun.

Wet places on mountain slopes, riversides, gully sides. Heilongjiang, Jilin, Liaoning, Nei Mongol [Korea, Russia (Far East, E Siberia)].