直穗薹草 zhi sui tai cao

Carex aristata R. Brown subsp. orthostachys (C. A. Meyer) Kükenthal.

Rhizome long stoloniferous. Culms laxly tufted, 40-70 cm tall, acutely triquetrous, rather thick, smooth or slightly scabrous on upper part, clothed with red-brown and bladeless sheaths at base, sheaths later splitting into fibers or reticulate fibers. Leaves shorter than culm, blades 3-5 mm wide, flat, revolute on margins, glabrous, with transverse septate nodes between veins on abaxial surface, sheathed, lower sheaths rather long. Involucral bracts leafy, slightly longer than or equaling inflorescence, shortly sheathed, setaceous at base of male spikes, usually shorter than spike. Spikes 5-7, upper ones approximate, lowermost one remote; terminal 2 or 3 spikes male, narrowly lanceolate or narrowly cylindric, 2-4 cm, subsessile; remaining spikes female, oblong-cylindric or cylindric, 3-6 cm, pedunculate, lower peduncles rather long, upper ones short. Female glumes pale ferruginous, brownish at middle, oblong-ovate or lanceolate, ca. 5 mm, membranous, 3-veined, apex acuminate, aristate, scabrous on margins of awn. Utricles stramineous, obliquely patent, longer than glume, ovate, inflated trigonous, 6-7 mm, thinly leathery, glabrous, distinctly several veined, base subrounded, shortly stipitate, apex gradually narrowed to a medium-sized to long beak, orifice rather long and strict 2-toothed. Nutlets loosely enveloped in utricle, elliptic-obovate, trigonous, ca. 2.5 mm, base shortly stipitate, apex mucronate; style base not thickened; stigmas 3. Fl. and fr. May-Jul.

Swamps, riversides, wet places. Hebei, Heilongjiang, Jilin, Liaoning, Nei Mongol, Xinjiang [Mongolia, Russia].