Description from Flora of China
Carex bullata Schkuhr subsp. laevirostris (Blytt ex Fries) Fries; C. bullata var. laevirostris Blytt ex Fries; C. laevirostris (Blytt ex Fries) Andersson.
Rhizome rather thick, stoloniferous. Culms 60-100 cm tall, stout, triquetrous, smooth on lower part, scabrid on upper part, clothed with brown or reddish brown sheaths at base. Leaves longer than culm, blades 8-15 mm wide, flat, slightly stiff, with short and transverse septate nodes, sheathed. Involucral bracts leaflike, longer than culm, lowermost involucral bract shortly sheathed, upper involucral bracts not sheathed. Spikes 7-11; terminal 3-7 spikes male, rather approximate, narrowly cylindric, 1.5-4.5 cm, sometimes with few female flowers at base, subsessile; remaining spikes female, cylindric, 3-7.5 × 1-1.5 cm, densely many flowered, sometimes with a few male flowers at apex, shortly pedunculate. Female glume brownish or yellowish brown, oblong-lanceolate, ca. 4.2 mm, membranous, costate, upper margins white hyaline, apex acute, muticous. Utricles yellow-green, horizontally patent in maturity, longer than glume, ovoid or broadly ovate, inflated trigonous, 6.5-7 mm, membranous, slightly nitid, glabrous, several veined, base subrounded, shortly stipitate, apex abruptly narrowed to a slightly long beak, orifice 2-toothed. Nutlets loosely enveloped in utricle, obovate, trigonous, ca. 2 mm, base shortly stipitate; style slender, flexuose, base not thickened; stigmas 3, rather shorter than style. Fl. and fr. Jun-Jul.
Wet places in swamps, at riversides, or at lakesides. Heilongjiang, Jilin, Xinjiang [Japan, Korea, Mongolia, Russia; Europe].