Erect annual, to 60 cm. Leaf-sheath green to purplish, chartaceous, keeled above, glabrous. Ligule 0; ligular area glabrous. Leaf-blade to 20 cm × 7 mm, flat, linear, glabrous, midrib distinct; margins scabrid, tapering to acute tip. Culm to 50 cm, sometimes branching below, internodes glabrous. Panicle to 14 cm, rather dense, erect, with spike-like racemes borne singly at lower nodes, shorter and more clustered above, florets strongly awned; rachis 3-angled, scabrid, long tubercle-based hairs at base of each raceme. Racemes 0.5–3 cm, erect, the lowest 1–2 distant, the rest approximate, bearing crowded spikelets; rachis 3-angled, very finely scabrid, with a few, long, tubercle-based hairs; pedicels very short, finely scabrid. Spikelets greenish to purple-suffused. Glumes quite unequal, submembranous, scabrid; lower c. 1 mm, 3–5-nerved, ovate, enwrapping base of spikelet, upper 3–4 mm, convex, 5-nerved with some bristle-like hairs on nerves, acuminate, cuspidate, or sometimes awned, awn to 3 mm. Lower floret: lemma similar to upper glume, 5–7-nerved, flat, nerves with tubercle-based spinules, almost always awned, awn 10–40 mm, purplish; palea < lemma, hyaline, keels ciliate. Upper floret: lemma to 3 mm, faintly 5-nerved, elliptic, convex, yellowish white, glabrous, shining, thinly crustaceous, shortly cuspidate; palea ≈ lemma and similar in texture, apex subobtuse; anthers c. 0.6 mm, brownish; caryopsis c. 2 × 1.3 mm, oblong, cream.
[From: Edgar and Connor (2000) Flora of New Zealand. Volume 5 (second printing).]