Tufted, rhizomatous or stoloniferous annuals or perennials. Ligule membranous. Inflorescence a loose or contracted panicle, persisting on the culm after maturity (cf. Lachnagrostis). Spikelets 1-flowered; glumes 2, persistent (except in A. viridis in which the spikelet falls intact), subequal, exceeding lemma, 1-nerved, keeled; rachilla not or only slightly developed, glabrous; lemma 3–5-nerved, firm or membranous, truncate or shortly bifid or 4-toothed, unawned or awned dorsally, usually near the base; palea membranous, shorter than the lemma, conspicuous (introduced species) or sometimes absent or nearly so (native species).
A cosmopolitan genus of ca 200 species, mostly from tempeate areas; 13 occurring in Australia (including 4 naturalized), 12 in Victoria.