Rhizomatous, loosely tufted, 20-40 cm. Rhizome horizontal, 1-2 mm diam., covered with dark, almost black-brown, finally fibrous scales. Stem robust, 2-3 mm in diam. at base, 0.8-1 mm above, sharply trigonous and usually scabrous above, obtusely trigonous below, deeply grooved. Leaves from c. ½ of stem length to c. equalling it; sheaths 30-60 mm, greyish-black, strongly nerved, margin of scarious side slightly oblique; ligule conspicuous, at margin to 1 mm, at middle up to 0.5 mm, scarious; blades 2.5-3.5 mm wide, yellow-green, flat or margin somewhat revolute, scabrous, at least upper surface papillose. Inflorescence 10-20 x 7-15 mm, light brown, cylindrical, sometimes almost globose, compact. Bracts inconspicuous, lowest of variable size, occasionally overtopping inflorescence, sheathless, narrow, scabrous. Spikes androgynous, individually difficult to distinguish, except lowest; female glumes 3-3.7 x 1.4-1.9 mm, cymbiform, acute or obtuse, margins scarious; utricles 3.3.-4 x 1.5-2 mm, with stipe to 0.5 mm ellipsoid or ovoid, plano-convex, yellowish brown or brown, with 5-9 strong, dark veins above and 3-5 below, glossy, conspicuously suberous all over, with narrow, scabrous wing in upper part; beak 0.5-1 mm, conical, with narrow, scabrous wings, bidentate or oblique, deeply split above, ostiole margins scarious. Nut 1.4-2 x 0.9-1.2 mm, ellipsoid or obovoid, bi-convex (or plano-convex), glossy, finely or obscurely reticulate.