4. Schoenus nudifructus C. Chen in Tang & F. T. Wang, Fl. Reipubl. Popularis Sin. 11: 230. 1961.
无刚毛赤箭莎 wu gang mao chi jian suo
?Perennials, tightly clumped. Roots slender fibrous. Culms tufted, erect, 55-100 cm tall, 0.8-1.1 mm thick, terete, smooth. Leaves basal, rarely also cauline. Basal leaf sheaths 1.5-2.5 cm, reddish black at base; leaf blade linear, 1-2 mm wide, papery, veins 7 and abaxially prominent. Cauline leaf sheaths brown, cylindric, 1.7-3 cm, glabrous, ligule absent. Involucral bracts leaflike; sheath brown; blade gradually shorter apically. Inflorescences paniculate, lax, branches 6 or 7 or more. Spikelets erect, narrowly ovoid, 7-9 mm, compressed, usually 2 or 3 or more clustered, ± pedunculate, 3- or 4-flowered. Glumes brownish red, lanceolate to ovate, keel abaxially yellowish green, margin pale, apex mucronate in basal glume and obtuse in apical glumes; basal 2 or 3 glumes empty, apical ones with 3 or 4 bisexual flowers. Perianth bristles absent. Stamens 3; anthers linear, deciduous. Style slender; stigmas 3, pubescent. Nutlet brownish, broadly ovoid to ovoid-oblong, 1-1.3 mm, 3-sided, reticulate, apex sparsely pubescent or glabrous. Fl. and fr. Jul.
● 1800-1900 m. C Yunnan (Kunming).