Poaceae
Bromus

Bromus japonicus Houtt.

First published in Nat. Hist. 2(13): 315 (1782)
This species is accepted
The native range of this species is Medit. to Temp. Eurasia. It is an annual or biennial and grows primarily in the temperate biome.

Descriptions

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation
Predicted extinction risk: not threatened. Confidence: confident
[AERP]

Morphology General Habit
Annual. Culms erect, or geniculately ascending; 35-70 cm long. Leaf-sheaths pubescent. Ligule an eciliate membrane. Leaf-blades 5-15 cm long; 3-6 mm wide.
Morphology Reproductive morphology Inflorescences
Inflorescence a panicle. Panicle open; ovate; effuse; 10-20 cm long; 5-10 cm wide. Primary panicle branches spreading, or drooping. Panicle branches multilateral, or secund; scabrous. Spikelets solitary. Fertile spikelets pedicelled.
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets comprising 7-15 fertile florets; with diminished florets at the apex. Spikelets ovate; laterally compressed; 15-35(-40) mm long; breaking up at maturity; disarticulating below each fertile floret.
Fertile
Spikelets comprising 7-15 fertile florets; with diminished florets at the apex. Spikelets ovate; laterally compressed; 15-35(-40) mm long; breaking up at maturity; disarticulating below each fertile floret.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 4-5 mm long; 0.66 length of upper glume; membranous; without keels; 3 -veined. Lower glume surface glabrous, or pubescent. Lower glume apex acute. Upper glume lanceolate; 6-7 mm long; 0.66-0.75 length of adjacent fertile lemma; membranous; without keels; 7 -veined. Upper glume surface glabrous, or pubescent. Upper glume apex acute.
Morphology Reproductive morphology Flowers Florets
Fertile lemma elliptic, or trullate; widest at 0.6 of its length from base; 8-12 mm long; coriaceous; much thinner on margins; without keel; 7 -veined. Lemma lateral veins obscure. Lemma surface glabrous, or pubescent. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn subapical; curved; spreading, or reflexed; flat below; 5-16 mm long overall (lower shorter). Palea keels ciliolate. Apical sterile florets resembling fertile though underdeveloped.
Morphology Reproductive morphology Flowers
Lodicules 2; membranous. Anthers 3; 0.75-1.5 mm long. Ovary with a fleshy appendage above style insertion; pubescent on apex.
Morphology Reproductive morphology Fruits
Caryopsis with adherent pericarp; hairy at apex; apex fleshy. Hilum linear.
Distribution
Europe: central, southwestern, southeastern, and eastern. Africa: north. Asia-temperate: Siberia, Soviet far east, Soviet Middle Asia, Caucasus, western Asia, China, Mongolia, and eastern Asia. Asia-tropical: India. Australasia: Australia. Pacific: north-central. North America: western Canada, eastern Canada, northwest USA, north-central USA, northeast USA, southwest USA, south-central USA, and southeast USA. South America: southern South America.
Reference
Bromeae. Fl Turk 1993.
[GB]

Sources

  • Angiosperm Extinction Risk Predictions v1

    • Angiosperm Threat Predictions
    • http://creativecommons.org/licenses/by/4.0

  • GrassBase - The Online World Grass Flora

    • Clayton, W.D., Vorontsova, M.S., Harman, K.T. and Williamson, H. (2006 onwards). GrassBase - The Online World Grass Flora.
    • http://creativecommons.org/licenses/by-nc-sa/3.0

  • Herbarium Catalogue Specimens

    • Digital Image © Board of Trustees, RBG Kew http://creativecommons.org/licenses/by/3.0/

  • Kew Backbone Distributions

    • The International Plant Names Index and World Checklist of Vascular Plants 2026. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0

  • Kew Names and Taxonomic Backbone

    • The International Plant Names Index and World Checklist of Vascular Plants 2026. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 International Plant Names Index and World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0

  • Kew Science Photographs

    • Copyright applied to individual images