Description from Flora of China
Rhizome with long stolons. Culms 20-40 cm tall, triquetrous, smooth on lower part, scabrid on upper part, clothed with red-brown and bladeless sheaths at base, rudimentary sheaths usually disintegrating into fibers. Leaves shorter than culm, blades 2-3 mm wide, flat, ± stiff, scabrous on margins, slightly long sheathed. Involucral bracts awn-shaped, usually shorter than spike, sometimes lowermost slightly longer than spike, not sheathed or lowermost one shortly sheathed. Spikes 3 or 4, congregate on top of culm; terminal 1 or 2 spikes male, oblong or clavate, 1-3 cm, sessile; remaining spikes female, ovate or oblong, 0.8-1.8 cm, densely many flowered, nearly sessile, sometimes lowermost one very shortly pedunculate. Female glumes brown laterally, yellowish brown at middle, orbicular-ovate or ovate, ca. 3.5 mm, membranous, 3-veined, green costate, margins white hyaline, sometimes upper margin erose, apex acute, mucronate. Utricles brown, obliquely patent, slightly longer than glume, broadly ovate or ovoid, obtusely trigonous, 3-4 mm, leathery, glabrous, slightly shiny, indistinctly veined, base subrounded, apex abruptly narrowed to a slightly broad and short beak, orifice shortly 2-toothed. Nutlets rather tightly enveloped in utricle, broadly obovate or broadly elliptic, trigonous, ca. 2.8 mm, base shortly stipitate, apex mucronate; style base not thickened; stigmas 3. Fl. and fr. Apr-Jun.
Dry mountains, grasslands, roadsides; 300-1000 m. Hebei, Heilongjiang, Henan, Jilin, Liaoning, Shaanxi, Shandong, Shanxi [N Korea].