Annuals or short-lived perennials, shoots extra-and intravaginal. Culms tufted, several, slightly arching, erect or geniculate at base, 4–35(–44) cm, 1–1.6 mm in diam., smooth, glabrous, nodes 1–3, none or 1 exserted, uppermost to 1/4 way up culm. Leaf sheaths thin, loose, soon withering, smooth, glabrous, 3–9 cm, ca. 2 × as long as blade, uppermost closed for 1/5–1/4 of length; blade flat or folded, thin, 2–8 cm × 1.5–3(–4) mm, surfaces smooth, margins and keel smooth to scabrid, apex acutely prow-tipped; ligules milky, ovate, 2–5 mm, abaxially smooth, glabrous, apex obtuse, entire to lacerate, collar smooth, glabrous. Panicle open, exserted, 3–7(–9) × 1.5–4 cm, longest internode 1–2 cm; branches spreading to reflexed, flexuous, often arched, 1 or 2(–3) per node, proximally sparsely scabrid, distally scabrid on and between angles, longest 1.5–4.5 cm with 9–25 spikelets in distal 1/2. Spikelets obovate, usually purple tinged, 2.5–4.5 mm, florets 2 or 3; vivipary absent; rachilla internodes 0.5–0.7(–1) mm, smooth or sparsely scabrid or pilulose; glumes lanceolate, subequal, upper often as long as or slightly longer than lower lemma, keel scabrid, surface smooth to distally sparsely scabrid, lower glume (1.5–)2.2–4 mm, 1-or 3-veined, upper glume (2–)2.3–5(–6) mm, 3-veined; lemmas broadly oblong, 2–4(–5) mm, intermediate veins distinct, keel shortly villous for 1/2–4/5 of length, marginal veins for 1/3–2/3, surfaces pilulose, sparsely scabrid near obtuse apex; callus glabrous or sparsely webbed; palea pilulose or minutely bumpy between keels, keels distally scabrid, pilulose for most of length. Anthers 0.6–1 mm. Fl. and fr. May–Aug.