Bromus diandrus Roth
Great Brome

Bot.Abh.Beobacht. 44-45 (1787)
Conservation Code
Not threatened
Naturalised Status
Alien to Western Australia
Name Status

Tufted annual, grass-like or herb, 0.2-0.7 m high. Fl. purple/yellow-green/cream, Aug to Nov. Yellow/grey/black sand, loam, red/brown clay.

Grazyna Paczkowska, Descriptive Catalogue, 31 October 1993


IBRA Regions
Avon Wheatbelt, Carnarvon, Coolgardie, Esperance Plains, Geraldton Sandplains, Jarrah Forest, Mallee, Nullarbor, Swan Coastal Plain, Warren, Yalgoo.
IBRA Subregions
Dandaragan Plateau, Eastern Goldfield, Edel, Fitzgerald, Geraldton Hills, Katanning, Lesueur Sandplain, Merredin, Northern Jarrah Forest, Nullarbor Plain, Perth, Southern Cross, Southern Jarrah Forest, Warren, Western Mallee, Wooramel.
IMCRA Regions
Abrolhos Islands, Central West Coast, Leeuwin-Naturaliste, Shark Bay, WA South Coast.
Local Government Areas (LGAs)
Albany, Armadale, Augusta Margaret River, Beverley, Boddington, Bridgetown-Greenbushes, Bunbury, Busselton, Canning, Capel, Carnamah, Chapman Valley, Cockburn, Coorow, Corrigin, Dandaragan, Dardanup, Donnybrook-Balingup, Dowerin, Esperance, Gingin, Gnowangerup, Goomalling, Gosnells, Greater Geraldton, Harvey, Jerramungup, Joondalup, Kalamunda, Kalgoorlie-Boulder, Katanning, Kwinana, Mandurah, Manjimup, Melville, Merredin, Mingenew, Murray, Nannup, Narembeen, Narrogin, Nedlands, Northam, Northampton, Perth, Pingelly, Plantagenet, Quairading, Rockingham, Serpentine-Jarrahdale, Shark Bay, South Perth, Swan, Tammin, Toodyay, Trayning, Wagin, Wanneroo, Waroona, Wickepin, Wongan-Ballidu, Woodanilling, Wyalkatchem, Yilgarn, York.

Management Notes (for the Swan NRM Region)

Alternative Names. Ripgut brome, giant brome, Kingston grass, brome grass.

General Biology. Growth form. Grass. Life form. Annual, caespitose. Reproduction. Seed. Dispersal. Mammals, wind, machinery, clothing, contaminated crop seed. Photosynthetic Pathway. C3. Seedbank persistence. Short, days to 2 years. Fire response. Unknown, however the seed remains in the inflorescence longer than most desirable grasses, where they are susceptible to direct heat from fire.

Notes. Naturalised across southern Australia due to aggressive spread and pre-adaptation to temperate Mediterranean climates. Similar to the native Bromus arenarius (sand brome) which has an earlier flowering period of July to October. Highly competitive for water, nutrients and space and adapted to a range of soil types from acidic to alkaline and sand to loams. Drought tolerant. Produces prolific seed. Seed remains dormant in high temperatures over summer but are highly germinable when conditions become suitable. Rainfall is the biggest determinant for germination. Most seed will germinate with first substantial rain in autumn/early winter. In dry starts to seasons, a greater proportion of the seeds show staggered germination which may continue until as late as August. Under increased nitrogen, seedlings emerge earlier at higher densities.

Additional information. Origin. Mediterranean. History of use/introduction. Introduced into Australia circa 1875 as a contaminant of crop seeds or wool. Similar exotic species. Bromus rigidus. Similar native species. B. arenarius.

Suggested method of management and control. Prevent seed set. Hand pull plants. In degraded areas use 1% glyphosate on seedlings, young plants or when flowering. Alternatively spray plants at 3-5 leaf stage with Fusilade® Forte at 16 ml/10 L or 800 ml/ha (based on 500 L water/ha) + wetting agent or for generic fluazifop-p (212g/L active ingredient) 10ml/10L or 500ml/ha + wetting agent. An early and late application may be required where two Bromus species are present. Repeat the following year if required. Read the manufacturers' labels and material safety data sheets before using herbicides. For further information consult the Australian Pesticides and Veterinary Medicines Authority to determine the status of permits for your situation or state.

Management Calendar

Calendar Type Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Comments
Active Growth           Y Y Y Y Y Y    
Germination         Y Y O O          
Flowering                 Y Y Y    
Fruiting                     Y Y  
Optimum Treatment           Y Y Y O O O    

Legend: Y = Yes, regularly, O = Occasionally, U = Uncertain, referred by others but not confirmed.



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