GrassBase - The Online World Grass Flora


W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Bromus hordeaceus

HABIT Annual; culms solitary, or caespitose. Culms erect, or geniculately ascending; 10–100 cm long; 2–9 -noded. Culm-nodes pubescent. Leaf-sheaths pubescent. Ligule an eciliate membrane; 1–3 mm long; erose. Leaf-blades 5–22 cm long; 2–7 mm wide. Leaf-blade surface hirsute.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; equilateral, or nodding; 1.5–16 cm long; 0.5–6 cm wide. Primary panicle branches bearing 1–7(–14) fertile spikelets on each lower branch. Panicle branches pubescent.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 2–10 mm long.

FERTILE SPIKELETS Spikelets comprising 6–12 fertile florets; with diminished florets at the apex. Spikelets ovate; laterally compressed; compressed slightly; 12–22 mm long; 3.5–6(–8) mm wide; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; shorter than spikelet; parallel to lemmas. Lower glume oblong, or ovate; 5–8 mm long; 0.8–0.9 length of upper glume; chartaceous; without keels; 3–7 -veined. Lower glume apex acute. Upper glume elliptic; 5–9 mm long; 0.7–0.8 length of adjacent fertile lemma; chartaceous; without keels; 5–7(–9) -veined. Upper glume apex acute.

FLORETS Fertile lemma elliptic, or obovate; 8–11 mm long; 2.5–5 mm wide; chartaceous; much thinner on margins; without keel; 7–9 -veined. Lemma lateral veins distinct. Lemma surface hirsute. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn subapical; 5–10 mm long overall; limb scabrous. Palea 0.8–0.9 length of lemma. Palea keels ciliolate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3; 0.2–2.5 mm long. Ovary with a fleshy appendage above style insertion; pubescent on apex.

FRUIT Caryopsis with adherent pericarp; fusiform; concealed by floret; hairy at apex; apex fleshy. Hilum linear; 1 length of caryopsis.

DISTRIBUTION Europe: northern, central, southwestern, southeastern, and eastern. Africa: north, Macaronesia, and south. Asia-temperate: Caucasus, western Asia, China, and eastern Asia. Asia-tropical: India. Australasia: Australia and New Zealand. Pacific: north-central. North America: Subarctic, western Canada, eastern Canada, northwest USA, north-central USA, northeast USA, southwest USA, south-central USA, southeast USA, and Mexico. South America: Brazil and southern South America. Antarctic: Subantarctic islands.

NOTES Bromeae. = Bromus mollis. Acedo 1996.

Please cite this publication as detailed in How to Cite Version: 3rd February 2016.