Plants rhizomatous. Culms 50–120 cm, erect; nodes 2–3(4), usually pubescent, sometimes glabrous; internodes glabrous or pubescent. Sheaths pilose, villous, or glabrous; auricles present on the lower leaves or absent; ligules to 3 mm; blades 9–17(25) cm long, (3)4–8(9) mm wide, abaxial surfaces glabrous or pilose, adaxial surfaces usually pilose, rarely glabrous. Panicles 10–20 cm, open or contracted, erect or nodding; branches erect to spreading. Spikelets 20–30 mm. Glumes glabrous, pubescent, or hirsute; lower glumes (4)5–9 mm, 1-veined; upper glumes (5)8–11 mm, 3-veined; lemmas 9–14 mm, pubescent on the lower portion of the back and along the margins; awns usually present, to 6 mm, sometimes absent; anthers 3.5–7 mm. 2n = 56.
Bromus pumpellianus subsp. pumpellianus grows on sandy and gravelly stream banks and lake shores, sand dunes, meadows, dry grassy slopes, and road verges.