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 interruptus

HABIT Annual; culms solitary, or caespitose. Culms erect, or geniculately ascending; 20–100 cm long; 2–4 -noded. Leaf-sheaths pubescent. Ligule an eciliate membrane; 1–2 mm long; erose. Leaf-blades 6–20 cm long; 2–6 mm wide. Leaf-blade surface pubescent.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; linear, or oblong; interrupted; equilateral; 2–9 cm long; 1–2 cm wide. Primary panicle branches 0.5–1.5 cm long; bearing 2–3 fertile spikelets on each lower branch.

Spikelets in pairs, or in threes. Fertile spikelets sessile; 2–3 in the cluster.

FERTILE SPIKELETS Spikelets comprising 5–11 fertile florets; with diminished florets at the apex. Spikelets oblong, or ovate; laterally compressed; compressed slightly; 10–15 mm long; 5–8 mm wide; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; shorter than spikelet; parallel to lemmas. Lower glume oblong; 5–7 mm long; 0.7–0.8 length of upper glume; chartaceous; without keels; 3–7 -veined. Lower glume apex acute. Upper glume elliptic, or ovate; 6–9 mm long; 0.8–1 length of adjacent fertile lemma; chartaceous; without keels; 5–9 -veined. Upper glume apex acute.

FLORETS Fertile lemma obovate; 7.5–9 mm long; chartaceous; much thinner on margins; without keel; 7–9 -veined. Lemma lateral veins distinct. Lemma surface pubescent. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn subapical; 4–8 mm long overall; limb scabrous. Palea readily splitting down midline; 0.8–0.9 length of lemma. Palea keels ciliolate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3; 1–1.5 mm long. Ovary with a fleshy appendage above style insertion; pubescent on apex.

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

DISTRIBUTION Europe: northern.

NOTES Bromeae. CEH.

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