A loosely tufted perennial; innovations extravaginal. Culms erect, 6 ft. or more high, stout, terete, pruinose towards and at the nodes, simple or branched from the upper nodes, up to 12-noded, finely striate, scaberulous and often sparsely hairy with stiff appressed or spreading hairs towards the inflorescence and below the upper nodes, otherwise glabrous and smooth. Leaf-sheaths longer than the internodes, terete, finely striate, the lower broad, pallid, papery, more or less hispid upwards with short tubercle-based hairs, at length glabrescent, the intermediate and upper ciliate on the margins towards the mouth or quite glabrous and smooth; ligule reduced to a densely ciliolate rim; blade linear, tapering to a slender acute tip, up to 2 1/2 ft. long and 5 lin. wide, flat or convolute when dry, firm, green, pilose at the back of the ligule, otherwise glabrous or with a few scattered hairs on the upper surface, scaberulous on the lower surface towards the tip and all over on the upper and along the margins, midrib broad and yellowish above, not prominent below. False spike dense, cylindric, straight or slightly flexuous, 11–13 in. long, 5–6 lin. wide (exclusive of the bristles), pale green and tinged with purple; rhachis finely ribbed, densely and minutely pubescent, rather densely studded with the minute hispidulous stumps of the deciduous involucres; involucres sessile, at length horizontally spreading or deflexed; bristles 15–50 to each involucre, very slender, free to the base, scaberulous, of unequal length, one stouter than the rest and up to 7 lin. long, the remainder varying in length and up to 4 lin. long. Spikelets sessile, mostly solitary within the involucre, lanceolate, acute, 2–2 1/2 lin. long, glabrous. Lower glume oblate and obtuse or ovate and acute, 1/4– 1/2 lin. long, hyaline, nerveless; upper ovate, acute or acuminate, sometimes mucronate, 1/2–1 1/2 lin. long, thinly membranous, 1–3-nerved. Lower floret barren: valve when flattened ovate to elliptic-ovate, acute, nearly as long as the spikelet, membranous, 5–7-nerved, minutely asperulous above the middle; valvule linear, 1 lin. long, or suppressed. Upper floret hermaphrodite, lanceolate, acute: valve when flattened elliptic, acute, as long as the spikelet, membranous, 5-nerved, minutely asperulous above the middle; valvule lanceolate, nearly as long as the valve. Lodicules minute. Anthers 1–1 1/4 lin. long, with glabrous tips. Styles connate or free for half their length.
