Flowering stems 25–110 cm long, glabrous or hairy at the nodes. Leaf sheaths hairy, the ligule 0.2–1.2 mm long. Leaf blades 4–18 cm long, 5–12 mm wide, usually glabrous. Inflorescences 5–16 cm long, with 5–20 spikelike racemes, these 1–3(–5) cm long. Spikelets 3.8–5.0 mm long, mostly in pairs along the axis of the raceme (single only toward the tip), lanceolate to narrowly ovate in outline, tapered to a narrow point at the tip. Upper glume 3.6–5.0 mm long, lanceolate to narrowly ovate, narrowed or tapered to a sharp point at the tip, awnless or with an awn 0.1–1.2 mm long, 5‑nerved. Sterile floret with the lemma 3.6–5.0 mm long, lanceolate to narrowly ovate, narrowed to a sharp point at the tip, awnless, 5‑ or 7‑nerved. Fertile floret with the lemma 2.3–3.3 mm long, oblong‑elliptic, rounded at the tip, but with a minute, triangular point 0.1–0.3 mm long. 2n=36. July–October.

Introduced, scattered in the Mississippi Lowlands Division and with a single collection from Johnson County (native of the southwestern U.S. east to Texas; Mexico; introduced in the southeastern U.S. north to Missouri, Illinois, and Kentucky). Crop fields, ditches, roadsides, and sandy, disturbed areas.

This species was known to Steyermark (1963) only from a single specimen from Scott County. During the past few decades it has become more common and widespread in the southern half of the state (especially along roadsides), particularly in southeastern Missouri. The other variety, var. minor (Vasey) R.B. Shaw, differs in its smaller, awnless spikelets and hairy leaf blades. It also occurs in the southwestern United States and Mexico but rarely is found as an introduction farther east.