39. Bromus squarrosus Linnaeus, Sp. Pl. 1: 76. 1753.
偏穗雀麦 pian sui que mai
Bromus wolgensis Fischer ex J. Jacquin; Forasaccus squarrosus (Linnaeus) Bubani; Serrafalcus squarrosus (Linnaeus) Babington.
Annual. Culms erect or geniculately ascending, 20–60 cm tall, 3–4(–5)-noded. Leaf sheaths pubescent; leaf blades flat, up to 15 cm × 2–5 mm, pubescent; ligule ca. 1 mm. Panicle lax, (5–)20 × 4–6 cm, usually 1-sided; branches few, shorter than or equaling spikelets, each bearing 1 or 2 pendent spikelets. Spikelets ovate, upper part gradually narrowed, (15–)20–50 × 5–15 mm, florets (6–)10–25; rachilla ca. 2 mm, smooth or scabrid; glumes oblong to elliptic, margins membranous, glabrous, lower glume 5–7 mm, 5-veined, apex acuminate, upper glume 6–8 mm, 9-veined, apex obtuse; lemmas obovate, 8–11 × (2–)3–6 mm in side view, 9-veined, glabrous or pubescent, margins white-membranous and angled near halfway point, apex entire or shallowly 2-toothed, awned from sinus ca. 2 mm below apex; awn 7–12 mm, longer on upper lemmas than lower lemmas, base flattened, slightly twisted, divaricate at maturity; palea 1/3 length of lemma, keels stiffly ciliate. Anthers 1–1.5 mm. Fl. and fr. May–Jul. 2n = 14.
Field margins, grasslands, waste ground; 500–3000 m. Gansu, Xinjiang [Kazakhstan, Mongolia, Russia; N Africa, SW Asia, Europe; introduced in America].
The name Bromus wolgensis has been applied to a variant with pubescent spikelets.