Plant dioecious, densely tufted; shoots intravaginal, basal sheaths straw-colored, glossy, not splitting into fibers. Culms 25–85 cm tall, nodes 1–3. Leaf sheaths glabrous; leaf blades usually flat, occasionally involute, 8–25(–40) cm × 2–3(–4.5) mm; ligule 0.1–0.3 mm. Panicle loose, lanceolate to ovate in outline, 6–14 cm; branches 3–7 cm, smooth, usually solitary, naked below middle. Spikelets 7–11 mm, purplish; florets 2–6; glumes entirely membranous except for narrow thicker band along vein; lower glume 3–4.5 mm; upper glume 4–6 mm; lemmas 6–8 mm, back asperulous, margins broadly membranous, apex obtuse to lacerate; awns absent or with 0.1–2 mm mucro. Anthers 2.7–4 mm in male florets. Ovary apex densely hairy in female florets. 2n = 28.