Tufted, sometimes shortly rhizomatous perennial; culms to 1.5 m high. Leaves smooth to scabrous; blade inrolled or flat, to 40 cm long, 2–4 mm wide; ligule acute, 4.5–8 mm long. Inflorescence a slender, rather sparse, erect panicle, 15–40 cm long. Spikelets 2–6-flowered, 8–17 mm long (excluding awns); glumes obtuse to acute, often purplish, the lower 3–5-nerved, 4–6.5 mm long, the upper 5–7-nerved, 5–7.5 mm long; lemma 5.9–8.5 mm long, finely scabrous, apical teeth 1–2 mm long, the outer pair commonly reduced or absent; awn 14–26 mm long, inserted within the upper third of the lemma, column strongly twisting, 4–7 mm long; palea slightly shorter than lemma. Flowers Oct.–Apr.