Stoloniferous perennial, 60-120 cm. Stem acutely trigonous, 1.5-3 mm diam., frequently papillose, smooth or scabrous along edges. Leaves to as long as stems; sheaths to 15 cm, septate, greyish brown, frequently with a red tint, disintegrating into fibres; ligule to 0.5 mm; blades (3-)4-6 mm wide, flat or margins revolute, long-acuminate, densely grey papillose below, margins and keel scabrous, upper surface smooth. Inflorescence with (1-)2-3 male and 2-3(-4) female spikes. Bracts sheath-less, lowest overtopping inflorescence. Male spikes (15-)20-40 x 3-5 mm, cylindrical, dark brown; glumes 4-5 x 1.3-1.6 mm, lanceolate, dark brown. Female spikes (15-)25-60 x 4-6 mm, cylindrical, erect or spreading-erect, lowest with peduncle to 40 mm; glumes 2.5-4 x 0.7-1.2 mm, ovate, acute or acuminate, dark-brown; utricles 2.8-4.1 x 1.6-2.1 mm, ellipsoid, greenish or greyish brown, sometimes with reddish tint, nerves prominent, upper part papillose and sometimes glandular punctate, beak 0.3-0.5 mm, cylindrical, papillose, shallowly bidentate. Stigmas 3, occasionally 2. Nut 1.8-2.3 x 1.2-1.3 mm, incl. c. 0.3 mm persistent style base, obovoid, trigonous, brown, finely reticulate with papilla in each areole.