Plants perennial; not rhizomatous. Culms 80–150 cm, erect; nodes 9–20, glabrous, usually concealed by the leaf sheaths; internodes usually glabrous, sometimes hairy just below the nodes. Sheaths overlapping, densely to moderately retrorsely pilose or glabrous over most of their surface, throats and collars densely pilose; auricles 1–2.5 mm on most lower leaves; ligules 0.8–1.4 mm, hirsute, ciliate, truncate, erose; blades 20–30 cm long, 5–15 mm wide, flat, usually glabrous, rarely pilose, with 2 prominent flanges at the collar. Panicles 10–22 cm, open, nodding; branches spreading to ascending. Spikelets 15–30 mm, elliptic to lanceolate, terete to moderately laterally compressed, with 4–9 florets. Glumes pubescent or glabrous; lower glumes 4–7.5 mm, 1(3)-veined; upper glumes 6–9 mm, 3-veined, sometimes mucronate; lemmas 8–14 mm, elliptic to lanceolate, rounded over the midvein, backs glabrous or pilose to pubescent, margins long-pilose, apices obtuse to acute, entire; awns 3–4.5(7) mm, straight, arising less than 1.5 mm below the lemma apices; anthers 2–3 mm. 2n = 14.
Bromus latiglumis grows in shaded or open woods, along stream banks, and on alluvial plains and slopes. Its range is mainly in the north-central and northeastern United States and adjacent Canadian provinces. Specimens with decumbent, weak, sprawling culms, densely hairy sheaths, and heavy panicles can be called Bromus latiglumis forma incanus (Shear) Fernald.