Rhizome with slightly thick stolons. Culms 45-60 cm tall, slightly thick, acutely triquetrous, scabrous on upper part, dark red-brown and bladeless sheathed at base, sheaths later usually splitting into reticulate fibers. Leaves longer than or equaling culm, blades 3-7 mm wide, flat, scabrous on adaxial surface and margins, with indistinctly transverse septate nodes between veins, long sheathed. Involucral bracts leafy, nearly equaling culm, not sheathed, sometimes lowermost involucral bract shortly sheathed. Spikes 4 or 5; terminal spike male, rarely male spikes 2, 3-4.5 cm, 2-3 mm thick; lateral spikes female, remote, distance between uppermost female spike and male spike 3.5-15 cm, female spikes 1.5-4.5 cm, 4-5 mm thick, densely many flowered, upper spike subsessile, lowermost spike shortly pedunculate. Female glumes brownish laterally, greenish at middle, slightly red-brown on upper part, ovate or ovate-lanceolate, 4-6 mm (including awn), membranous, 1-3-veined, margins white hyaline, apex acuminate, aristate or mucronate, scabrous on margins of awn or mucro. Utricles gray-brown, obliquely patent, equaling or slightly shorter than glume, oblong-ovate, slightly inflated trigonous, ca. 4 mm, membranous, hispid, 5-veined, base abruptly contracted, subrounded, shortly stipitate, apex gradually narrowed to a long and slightly broad beak, beak scabrous on margins, 2-toothed and red-brown at orifice. Nutlets tightly enveloped, obovate, trigonous, 1.5-1.8 mm, apex curved mucronate; style base slightly thickened; stigmas 3, slightly long. Fl. and fr. Apr-May.