Plant caespitose. Stems 450-710 mm, sharply trigonous above, smooth. Leaves slightly shorter, as long as or longer than stems, (4.7) 6.0-10.0(11.1) mm wide, plicate, soft, scabrid on the edges, except basal parts, and on both faces in the apical part; ligule 1-3(8) mm, apex usually rounded, rarely subacute; antiligule absent; lowermost sheaths of the flowering stems foliose, the 2-3 lower most of the sterile shoots scale-like, straw-coloured to light brown, entire to slightly fibrose. Inflorescence 180-350 mm. Lowest bract slightly longer or shorter than inflorescence; sheath 22-55 mm long, the inner side green. Spikes 5-6, heteromorphic, with 1 apical male or androgynecandrous, sometimes with a small male or androgynous spike at its base, and 4-5 lateral female. Apical spike 30-45 mm x 1.8-8.7 mm, fusiform. Female spikes 28-51 x 5-8 mm, arising singly, dense-flowered except sometimes in basal parts, the lowest with a peduncle up to 185 mm, the 1-3 lowest pendulous. Male glumes 5.0-6.2 x 1.0-1.8 mm, lanceolate, narrowly ovate or oblong-elliptic, hyaline to straw-coloured, with a narrow green midrib, uninervate, acuminate to aristate. Female glumes (3.0) 3.5-4.0(5.0) x (1.1)1.3-1.8 mm, ovate, hyaline, with a narrow green midrib, 1-3 nervate, aristate, with an arista up to 1.5(1.8) mm, sometimes reduced to a short mucro. Utricles (3.0)4.0-4.5 x (1.0)1.2-1.6 mm, ovate to ellipsoid-trigonous, straight, with 2 well marked nerves, sometimes with some additional faint nerves, abruptly narrowed into a beak, greenish-brown; beak 1.2-2.0 mm, slightly bidentate to nearly truncate, with a deeper dorsal sinus, smooth. Achenes 2.0-2.8 x 1.11.3 mm, elliptic, trigonous.