Perennial, up to 2 (rarely 4) ft. high; rhizome long, creeping, innovation-shoots mostly extra-vaginal, often growing into long stolons. Culms erect or ascending, glabrous, many-noded, simple or branched at the base, the barren shoots densely and distichously leafy. Leaf-sheaths generally exceeding the internodes, the lower more or less loose, wide and tough, the upper tight, all ciliate along the margins, otherwise usually smooth and glabrous or the lower more or less finely hirsute or pubescent, with tubercle-based hairs; ligule a membranous ciliate rim; blades linear, shortly tapering to a callous point, 2 1/2–6 in. by 1 1/2–3 lin., usually involute, very firm and rigid, spreading, glaucous, glabrous or hairy, particularly on the upper surface downwards, margins cartilaginous, smooth or appressedly spinulose and sparingly tubercled near the base, very closely and finely nerved, midrib and primary nerves very slender if at all differentiated. Panicle usually contracted, erect and stiff, rarely slightly nodding, 3–8 in. long, glabrous, divided to the third or (downward) fourth degree; main axis and all divisions glaucous, increasingly filiform, angular and upwards scaberulous or scabrid, often somewhat wavy; primary branches usually erect, solitary or approximate in pairs or threes, the lower mostly remote and 2–6 in. long, sparingly divided, the penultimate divisions forming loose or contracted 6–2-spiculate racemes; pedicels with subcupular tips, the lateral about 1 1/2 lin. long. Spikelets ovate-oblong, acute to subacuminate, 1–1 3/8 lin. long, glabrous, pale. Glumes very unequal; lower subhyaline, whitish, very broad, clasping, rounded or shortly acute, midnerve very slender, percurrent, side-nerves 1–4 on each side, very short and fine; upper thin, membranous except at the firmer tip, broadly rounded on the back, corresponding in shape and size to the spikelet, 9–7-nerved, nerves prominent upwards. Lower floret ♂: valve very like the upper glume but less acute or acuminate, 9-nerved; valvule subequal, oblong, obtuse to acute; anthers up to almost 1 lin. long. Upper floret hermaphrodite, elliptic-oblong, subacute, 1 lin. long, white, smooth and glossy: valve and valvule coriaceous-crustaceous, faintly 7-nerved. Grain white, 3/4 lin. long.
