Bald Brome

Annual. Culms slender, loosely tufted, erect or ascending, 25–80(–100) cm tall, glabrous or pubescent, 2–5-noded. Leaf sheaths hairy toward base, upper sheaths sparsely hairy or glabrous; leaf blades 5–30 cm × 2–8 mm, pubescent; ligule 1–3 mm. Panicle erect, narrow, 12–15 × 2–4 cm, sometimes nodding at maturity; branches 2–6 per node, lowest up to 6 cm, each bearing 1–4 spikelets. Spikelets oblong, slightly compressed, 12–20 × 4–6 mm, florets 5–10, overlapping; glumes unequal, apex acuminate, lower glume 4–6 mm, 3-veined, upper glume 4.5–7 mm, 5–7-veined; lemmas elliptic, 6–10 × 2–2.5 mm in side view, scabrid, 7–9-veined, apex obtuse, awned from ca. 1 mm below apex; awn 3–9 mm, straight; palea shorter than lemma. Anthers 1.5–3 mm. Caryopsis thin, flat, ca. 7 × 2 mm, slightly shorter than palea. Fl. and fr. Jun–Aug. 2n = 14, 28, 56.

Gansu, Qinghai, Xinjiang, Xizang [Afghanistan, Bhutan; N Africa, Europe].

River valleys, moist grasslands, roadsides, grassy places; 2700–4400 m.

Brachypodium commutatum (Schrader) P. Beauvois; Bromus arvensis Linnaeus var. racemosus (Linnaeus) Neilreich; B. commutatus Schrader; B. mollis Linnaeus var. com-mutatus (Schrader) Sanio; B. mutabilis F. W. Schultz var. com-mutatus (Schrader) F. W. Schultz; B. popovii Drobow; B. racemosus subsp. commutatus (Schrader) Maire & Weiller; B. racemosus var. commutatus (Schrader) Cosson & T. Durand; B. squarrosus Linnaeus var. racemosus (Linnaeus) Regel; Forasa-ccus commutatus (Schrader) Bubani; F. racemosus (Linnaeus) Bubani; Serrafalcus commutatus (Schrader) Babington; S. race-mosus (Linnaeus) Parlatore; S. racemosus subsp. commutatus (Schrader) Rouy; S. racemosus var. commutatus (Schrader) Husnot.