Perennial, densely or compactly cæspitose, up to over 4 ft. high, with intravaginal innovations. Culms firm and somewhat stout, terete, glabrous and smooth, simple and 4-noded below the panicle. Leaf-sheaths terete with broad rounded shoulders, very tight, glabrous or the lowest shortly and appressedly hairy, the basal up to 1/2 ft. long, inrolled, long-persistent; ligules very short, scarious, ciliolate; blades linear from a somewhat narrowed or slightly constricted base, tapering to a long point, up to 1 ft. long, 1 1/2–3 lin. wide, flat or the upper tightly convolute when dry and then almost filiform, firm, rigid, glabrous, smooth except at the scabrid margins; midrib slender, hardly prominent below, whitish above, lateral nerves numerous and prominent above, obscure below. Spatheate panicle very narrow, lax, up to over 2 ft. long, of about 4–5 very distant tiers (the lowest internode almost 1 ft. long); the lowest 1 or 2 tiers reduced to 1 or 2 compound 1–2-noded rays up to over 1 ft. long, the following of 5–7 simple rays; lower subtending leaves resembling the preceding ones, with filiform convolute blades. Spatheoles very narrowly lanceolate, long-acuminate, 2–3 in. long, 1 1/2 lin. wide, scarious, reddish, glabrous, at length loosely inrolled from the margins; peduncles filiform, erect and more or less straight, sparingly and shortly hairy towards the tips, 8–10 lin. long. Racemes laterally exserted from the spatheoles, at length diverging, sharply epinastically reflexed, somewhat loose, about 1 in. long, 6–8-awned per pair, greenish, variously tinged with purple or brown, glabrous except for the silky cilia of the joints and pedicels; bases linear-filiform, the lower 1/2 lin., the upper up to 1 1/2 lin. long, pubescent in the fork, tips truncate, shortly bearded, without an appendage; joints filiform, very obliquely truncate, up to almost 2 lin. long, shortly silkily ciliate; pedicels similar, more slender and slightly shorter. Homogamous pairs of spikelets 1 at the base of each raceme. Fertile spikelets linear-lanceolate to linear-oblong, 4 lin. long including the callus, glabrous; callus slender, acute, 1 lin. long, grooved on the back, very shortly bearded. Glumes equal, chartaceous; the lower minutely truncate and 2-denticulate, very smooth and somewhat glossy on the back, finely 11–13-nerved, with the nerves very obscure except in transmitted light, margins narrowly involute, keels very fine and obscurely scaberulous towards the tips; upper glume obliquely truncate, sometimes mucronulate, 3-nerved, sparingly ciliate. Lower floret reduced to an oblong obtuse 2-nerved spreadingly ciliate hyaline valve as long as the glumes. Upper floret hermaphrodite: valve substipitiform, 2-dentate, teeth 1/2 lin. long, sparingly ciliate; awn 1 1/4–1 3/4 in. long, slender; column brown, puberulous, bristle pale; valvule 0. Pedicelled spikelets lanceolate, acute, 3 1/2–4 lin. long, glabrous; lower glume chartaceous, 9-nerved, intracarinal nerves about 5, keels always smooth, upper acute, 3-nerved, spreadingly or reversedly ciliate; valves oblong, hyaline, ciliate, lower acute, sub-3-nerved, upper emarginate or 2-lobed, 1-nerved; anthers over 2 lin. long.