Plants annual. Culms 80–110 cm, erect. Lower sheaths densely, softly appressed-hairy; ligules 1–1.5 mm, hairy, obtuse, erose; blades 10–20 cm long, 2–6 mm wide, coarsely pilose on both surfaces. Panicles 11–30 cm long, 4–20 cm wide, open, erect or nodding; branches usually longer than the spikelets, ascending to widely spreading, slender, slightly curved or straight. Spikelets10–25 mm, lanceolate, terete to moderately laterally compressed, often purple-tinged; florets 4–10, bases concealed or visible at maturity; rachilla internodes concealed or visible at maturity. Glumes glabrous; lower glumes 4–6 mm, 3-veined; upper glumes5–8 mm, 5-veined; lemmas 7–9 mm long, 1.1–1.5 mm wide, lanceolate, obscurely 7-veined, rounded over the midvein, glabrous, coriaceous, margins slightly angled, inrolled or not at maturity, apices acute, bifid, teeth shorter than 1 mm; awns 6–11 mm, straight, arising at varying distances below the lemma apices; anthers 2.5–5 mm. Caryopses shorter than the paleas, weakly to strongly inrolled. 2n = 14.
Bromus arvensis grows along roadsides and in fields and waste places. It is native to southern and south-central Europe.