Field Brome

Plant / resting place / within
puparium of Cerodontha incisa may be found in leaf-mine of Bromus arvensis

Annual. Culms loosely tufted, 40–100 cm tall, 2–5-noded. Leaf sheaths hairy; leaf blades 10–20 cm × 3–6 mm, scattered pubescent, margins and adaxial surface scabrid; ligule 2–4 mm. Panicle lax, 15–30 × 10–20 cm; branches clustered, spreading or nodding, scabrid, each bearing 5–8 spikelets. Spikelets oblong-lanceolate, 12–22 × 3–4 mm, tinged with purple, florets 5–8, overlapping; rachilla ca. 2 mm; glumes unequal, margins membranous, apices acuminate, lower glume 4–6 mm, 3-veined, upper glume 6–8 mm, 5–7-veined; lemmas broadly elliptic or obovate, 7–9 mm, back rounded, 7-veined, glabrous, margins membranous with obtuse angle, apex minutely 2-toothed, awned from ca. 2 mm below apex; awn 7–10 mm, slender, straight; palea subequal to lemma, keels ciliate. Anthers 3–4.5 mm. Caryopsis blackish brown, 7–9 × ca. 1 mm. Fl. and fr. Jun–Aug. 2n = 14.

Roadsides, fields, forest margins, moist places. Gansu, Jiangsu [Russia; N Africa, SW Asia, Europe; introduced in America].

Avena arvensis (Linnaeus) Salisbury; Bromus arvensis Linnaeus var. phragmitoides (A. Nyárady) Borza; B. erectus Hudson var. arvensis (Linnaeus) Hudson; B. phragmitoides A. Nyárady; Forasaccus arvensis (Linnaeus) Bubani; Serrafalcus arvensis (Linnaeus) Godron.

Annuals, Terrestrial, not aquatic, Stems nodes swo llen or brittle, Stems erect or ascending, Stems solitary, Stems caespitose, tufted, or clustered, Stems terete, round in cross section, or polygonal, Stem internodes hollow, Stems with inflorescence less than 1 m tall, Stems, culms, or scapes exceeding basal leaves, Leaves mostly cauline, Leaves conspicuously 2-ranked, distichous, Leaves sheathing at base, Leaf sheath mostly closed, Leaf sheath hairy, hispid or prickly, Leaf sheath and blade differentiated, Leaf blades linear, Leaf blades 2-10 mm wide, Leaf blades mostly flat, Leaf blades more or less hairy, Leaf blades scabrous, roughened, or wrinkled, Ligule present, Ligule an unfringed eciliate membrane, Inflorescence terminal, Inflorescence an open panicle, openly paniculate, branches spreading, Inflorescence a contracted panicle, narrowly paniculate, branches appressed or ascending, Inflorescence solitary, with 1 spike, fascicle, glomerule, head, or cluster per stem or culm, Inflorescence lax, widely spreading, branc hes drooping, pendulous, Inflorescence with 2-10 branches, Flowers bisexual, Spikelets pedicellate, Spikelets laterally compressed, Spikelet 3-10 mm wide, Spikelets with 3-7 florets, Spikelets with 8-40 florets, Spikelets solitary at rachis nodes, Spikelets all alike and fertille, Spikelets bisexual, Spikelets disarticulating above the glumes, glumes persistent, Spikelets disarticulating beneath or between the florets, Rachilla or pedicel glabrous, Glumes present, empty bracts, Glumes 2 clearly present, Glumes equal or subequal, Glumes distinctly unequal, Glumes shorter than adjacent lemma, Glumes 3 nerved, Glumes 4-7 nerved, Lemmas thin, chartaceous, hyaline, cartilaginous, or membranous, Lemma 5-7 nerved, Lemma glabrous, Lemma apex dentate, 2-fid, Lemma distinctly awned, more than 2-3 mm, Lemma with 1 awn, Lemma awn less than 1 cm long, Lemma awn subapical or dorsal, Lemma awns straight or curved to base, Lemma margins thin, lying flat, Lemma straight, Palea present, well developed, Palea membranous, hyaline, Palea about equal to lemma, Palea 2 nerved or 2 keeled, Palea keels winged, scabrous, or ciliate, Stamens 3, Styles 2-fid, deeply 2-branched, Stigmas 2, Fruit - caryopsis, Caryopsis ellipsoid, longitudinally grooved, hilum long-linear, Caryopsis hairy at apex.

Bromus arvensis, the field brome, is a brome grass native to Europe and Asia. The specific epithet arvensis is Latin, meaning "of cultivated land".