Plants 450–800 mm tall, caespitose, with tufts connected by long rhizomes. Rhizomes very short within tufts, long between tufts, 5 mm in diameter. Shoot scales and basal leaves not developing extensive anthocyanin coloration (or sometimes small patches). Leaves mid-green, glaucous, usually without conspicuous transverse venation. Basal leaf sheaths folded, old sheaths becoming spongy; inner face splitting into connected fibrillae. Largest basal leaf blade 550 × 5–10 mm, flat or plicate in cross-section; adaxial surface glabrous; abaxial surface papillate; margins proximally glabrous, distally minutely scabrid. Lowest culm leaf: sheath mouth concave, herbaceous; ligule 14 mm high, whitish, stramineous, or fuscous, membranous, apex acute. Culms sharply triangular in cross-section, 2–3 mm in diameter; uppermost internode very long, the lower all more-or-less basal, very short, concealed by leaf sheaths. Inflorescence a raceme of spikes, 130–400 mm long. Basal inflorescence bract leaf-like, not reflexed near base of blade at maturity, not sheathing; blades 140–570 mm long; opposing bracteole tubular, membranous, usually concealed by bract sheath. Primary inflorescence units 1 from each node. Spikes 5–7, erect or suberect, not clustered, excepting frequently apical 2–3 (usually staminate) spikes; the largest 300–800 × 4–8 mm. Longest peduncle exserted by 0–50 mm, scabrid on angles. Apical spikes usually staminate. Staminate spikes 1–3. Pistillate spikes (1–)3(–4). Bisexual spikes 0–2. Small accessory spikes not present. Bracts of staminate spikelets extremely dimorphic. Anthers 2.5–4.0 mm long. Bracts of pistillate spikelets lanceolate, 3.0–5.5 mm × 0.6–1.2 mm, longer and narrower than perigynium, ferruginous, glabrous, but ciliate distally on margin; carina broad, 3-nerved; apex acuminate or emarginate, awned; awn 1.3–3.0 mm long, margin scabrid. Mature perigynium suberect, stipitate, without a basal callus, rostrate, 3–4 a 1.6–2.0 mm, triangular in cross-section, not inflated, greyish green with rostrum whitish, base without a layer of corky material, cartilaginous, papillate, with hollow papillae; nerves conspicuous, many (more than 10); rostrum abrupt, 0.8–1.0 mm long, straight, margin not winged, glabrous; apex shallowly bidentate, apical teeth 0.3 mm long. Rachilla absent from perigynia. Style base straight; stigmas 3. Mature nutlet obovate, not clawed, 1.7–2.0 × 1.2–1.5 mm, triangular in cross-section, yellowish-brown, glabrous.