228. Carex tenuiformis H. Léveillé & Vaniot, Bull. Acad. Int. Géogr. Bot. 11: 104. 1902.
细形薹草 xi xing tai cao
Carex koreana Komarov.
Rhizome short. Culms densely tufted, 20-40 cm tall, rather slender, obtusely trigonous, smooth, slightly scabrous at upper part, closed at base with brownish or red-brown sheaths, old sheaths usually disintegrated into fibers. Leaves slightly shorter than culm, blades 2-2.5 mm wide, flat, rather soft, scabrous on margins, rather long sheathed. Involucral bracts leaflike, usually shorter than subtending spike, sheathed, rather long. Spikes 3, rather remote; terminal spike male, lanceolate or broadly linear, 1.2-1.7 cm, conspicuously longer than adjacent female spike; lateral spikes female, broadly linear or oblong-linear, 1.5-2 cm, loosely 10- to more flowered; peduncle slender, up to 6 cm, slightly scabrous, slightly pendent or erect. Female glumes ferruginous, elliptic or obovate-oblong, 2.5-3 mm, membranous, green 1-veined, margins broadly hyaline at upper part, apex obtuse or acute. Utricles yellowish green, suberect, longer than glume, oblong-lanceolate, compressed trigonous, 3.5-4.5 mm, membranous, nerveless or 2-veined laterally, gradually tapering to a short stipe at base and a long beak at apex, beak scabrous on margins, obliquely truncate at orifice, slightly ferruginous. Nutlets rather loosely enveloped, obovate, trigonous, ca. 2 mm, apex mucronate; style base slightly thickened; stigmas 3. Fl. and fr. Jun-Jul.
Forests, grasslands on forest margins or in thickets, sometimes on mountain slopes. Heilongjiang, Nei Mongol [Japan, Korea, Russia (Far East, E Siberia)].