Annuals or perennials; culms erect or ascending, often with groups of short internodes; ligule membranous. Leaf-blades expanded or rolled. Inflorescence secund spikes with terminal spikelet; spikes digitate, or in 1 or 2 whorls. Spikelets sessile, laterally compressed, alternate or ventral side of rachis, with upper glume on exterior side, 1-5-flowered; lowest floret bisexual, second bisexual or empty, all higher florets male or empty; rachilla articulate below lower lemma, callus usually bearded, glumes narrow, keeled, 1-nerved, persistent; lower glume acute, smaller than upper glume; upper glume entire or emarginate, often mucronate or with short awn; lower lemma narrow or broad, 3-nerved, acute or obtuse, shortly bidentate, usually with an imperfect awn just below apex, margins often ciliate; lower paleas usually of same length as lemma, 2-keeled; lodicules 2, small; stamens 3; ovary glabrous, the styles 2, short, the stigmas laterally exserted; upper lemma and higher lemmas smaller than lower lemma, usually glabrous, awned or not, often epaleate and black at maturity. Caryopsis crowned by thickened base of style, narrowly ovate in profile, usually triquetrous; pericarp very thin, hyaline, free, embryo rather large; hilum punctiform.
About 40 species distributed in tropical and warm temperate regions. Several are useful pasture grasses.
Four species are found on the plains, among which C. gayana is considered one of the best forage grasses, and it is also used as the soil bander at mountain area since the big earthquake of Sept. 21, 1999 in Taiwan.