Caespitose, short-lived perennial without rhizomes or stolons; culms up to 90 cm tall, erect, ascending or decumbent and rooting from the nodes, usually branched, glabrous at the nodes, eglandular or with a ring of small coalescent glandular patches below the nodes; basal leaf sheaths glabrous, chartaceous, ± compressed and keeled, gland-dotted on the nerves, persistent; ligule a line of hairs; leaf laminas 5–20 cm × 3–5 mm, linear, flat or involute, glabrous, eglandular.Panicle 11–23 cm long, narrow and contracted or open and effuse, stiffly branched, the spikelets evenly distributed on pedicels 1.5–2.5 mm long, these with a conspicuous annular gland, the primary branches not in whorls (but often paired or loosely clustered), terminating in a fertile spikelet, glabrous in the axils.Spikelets 4–7 × 1–1.5 mm, narrowly oblong, lightly laterally compressed, 4–13-flowered, the lemmas disarticulating from below upwards, the rhachilla persistent below, becoming fragile above; glumes subequal, 1.2–1.6 mm long, lightly keeled, narrowly oblong-ovate in profile, scaberulous on the keel, obtuse at the apex, the inferior reaching to just beyond the middle of the adjacent lemma, the superior to just short of the middle; lemmas 1.4–1.6 mm long, lightly keeled, ovate-elliptic in profile, membranous with prominent lateral nerves, appressed to the rhachilla, those in opposite rows ± imbricate and concealing the rhachilla, usually leaden-grey, rarely pallid, faintly scaberulous on the back, obtuse to almost truncate at the apex; palea persistent, glabrous on the flanks, the keels slender, wingless, scaberulous; anthers 3, c. 0.7 mm long.Caryopsis 0.5–0.6 mm long, broadly elliptic to almost square.
