Plants stoloniferous. Culms 1-1.5 m tall, ca. 1 cm thick, sharply 3-angled, angles slightly winged, base clothed with long leaf sheaths. Leaf blade 40-60 × ca. 0.8 cm, abaxially ribbed, basally folded. Involucral bract 1, culmlike, to 25 cm, erect, greatly overtopping inflorescence, obtusely 3-angled. Inflorescence a pseudolateral head, ± dense, with 3-5 spikelets. Spikelets oblong to oblong-ovoid, 8-10 × 2-3 mm, 10-flowered. Glumes brown, broadly ovate to elliptic, ca. 5 mm, membranous, margin white hyaline, apex emarginate with a 1-veined costa excurrent into a short awn. Perianth bristles 6, longer than nutlet, retrorsely scabrous. Stamens 3; anthers linear, ca. 2 mm. Style slender; stigmas 3, shorter than style. Nutlet broadly ovoid, ca. 2 mm, plano-convex. Fl. and fr. Aug-Oct.
Near water margins. Gansu, Hebei, Ningxia, Shandong, Xinjiang [Kazakhstan, Russia; E Europe].