Perennial, 50-125 cm. Rhizome creeping or stoloniferous, 2-4 mm diam., brown or reddish brown. Stem 2-6(-10) mm diam., distal parts sharply, proximal parts obtusely trigonous, smooth, glaucous green. Sheaths 3, ephemeral, green or often with reddish tint, mouth deeply oblique, margins widely scarious; blades mostly reduced to mucro, uppermost up to 50 mm, channelled, smooth, apex obtusely pointed. Inflorescence of (1-)3-7 sessile spikes, 15-25 mm diam., or a multiple spike; lowest bract to c. 35 mm, trigonous, smooth; primary branches 0-7, up to 30 mm, each with (1-)2-4 sessile spikes; secondary branches occasional, up to 8 mm. Spikes 8-12 x 4-7 mm, ovoid; glumes rather loosely imbricate, 3-4.1 mm, cymbiform, mid-nerve mostly smooth, mucro barbed, up to 0.8 mm, sides inconspicuously nerved, brown or yellowish brown, smooth, apex rounded, often truncate, margins scarious, ciliate. Perianth bristles 4-6, about equalling nut; stamens 3, anthers 1.5-2 mm; stigmas 2. Nut 2.2-3.2 x 1.3-2 mm, ellipsoid or ovoid, bi-convex or almost plano-convex, smooth, yellow brown, glossy.