Many-tufted perennials, with mostly inclined culms from an extremely short, slender, knotted, wiry rhizome. Leaf-sheath light green, or distinctly red, or purplish, keeled, submembranous, smooth, sometimes minutely scabrid above; margins glabrous. Ligule ciliate, hairs 0.5-1.2 mm. Collar hairs few, long, tubercle-based. Leaf-blade 5-15 cm × 1.5-6 mm, flat, linear, twisted in upper ½, tapering to scabrid, narrowly acuminate tip, often glaucous, abaxially with obvious midrib, smooth to somewhat scabrid, adaxially scabrid. Culm (2)-20-60 cm, slender, somewhat compressed, internodes very short-pubescent to scabrid just below panicle. Panicle (1.5)-2.5-8.5 cm × 3-8 mm, narrow-cylindric, dense-flowered; rachis densely, softly scabrid-pubescent, with numerous very short branches each bearing a single spikelet subtended by 4-7 unequal, whitish or yellowish, antrorsely scabrid bristles (1.5)-2.5-6 mm. Spikelets 2.2-3 mm, pale green, elliptic, acute. Glumes broadly ovate, obtuse to subacute or apiculate; lower 1-2 mm, 3-nerved, usually < ½ but occasionally to ⅔ length of spikelet, upper 1.5-2.5 mm, 5-nerved, usually ¾ length to occasionally ≈ spikelet. Lower floret: lemma 5-(7)-nerved, ovate; palea = lemma, keels glabrous, rounded. Upper floret: lemma ≈ spikelet, sometimes apiculate, indurated, transversely rugose with close, narrow ridges, convex, greenish at first, later purple-tipped; palea ≈ lemma, somewhat indurated, very finely rugose, keels thickened, smooth except for a few minute prickle-teeth near apex, margins hyaline; anthers 0.6-0.9 mm; caryopsis 1-1.5 mm.

Laxly tufted often straggling annuals, 18-85 cm, yellow-green, often purplish near base. Leaf-sheath compressed, keeled, submembranous to firm, striate, glabrous. Ligule ciliate, hairs to 1 mm. Leaf-blade (3)-8-15-(20) cm × 2-5 mm, flat, soft, abaxially glabrous, adaxially minutely prickle-toothed on ribs, with a few long (to 8 mm) hairs near base; margins and midrib minutely prickle-toothed above, tip long-tapered, acuminate. Culm 10-30-(75) cm, ± erect, nodes compressed, often dark brown, internodes ridged, glabrous, minutely prickle-toothed to pubescent on ridges just below panicle. Panicle 2-5-(8.5) cm × 6-18 mm, cylindric, dense-flowered; rachis hispidulous, with many, short, close-set, hispidulous branches bearing clusters of 2-3, almost sessile spikelets, each spikelet subtended by 6-11 tawny or reddish brown to purplish, antrorsely scabrid bristles (2-8 mm). Spikelets 2.2-2.4 mm, light green, falling entire at maturity. Lower glume 0.7-1.2 mm, ovate, acute or apiculate, 3-nerved, upper 1-2 mm, ovate-orbicular, obtuse, 3-(5)-nerved. Lower floret Ø: lemma 5-nerved, acute; palea ≈ lemma, hyaline. Upper floret ☿: lemma = spikelet, very convex, crustaceous, finely rugulose, pale cream, sometimes apiculate; palea of same texture but ≤ lemma, keels rounded, glabrous; anthers (0.7)-0.9-1.2 mm; caryopsis c. 1.5 × 1.0 mm.