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Lolium rigidum Gaudin
Wimmera Ryegrass

Agrost.Helv. 1:334-335 (1811)
Conservation Code
Not threatened
Naturalised Status
Alien to Western Australia
Name Status

Erect or spreading annual, grass-like or herb, 0.3-1 m high. Fl. green-yellow, Sep to Nov. White or brown sand, sandy clay, gravelly loam. Roadsides, dunes, winter-wet flats, lake edges.

Grazyna Paczkowska, Descriptive Catalogue, 24 November 1993


IBRA Regions
Avon Wheatbelt, Esperance Plains, Geraldton Sandplains, Jarrah Forest, Mallee, Swan Coastal Plain, Warren.
IBRA Subregions
Eastern Mallee, Fitzgerald, Geraldton Hills, Katanning, Merredin, Northern Jarrah Forest, Perth, Recherche, Southern Jarrah Forest, Warren, Western Mallee.
IMCRA Regions
Central West Coast, Leeuwin-Naturaliste, WA South Coast.
Local Government Areas (LGAs)
Albany, Armadale, Bruce Rock, Bunbury, Busselton, Canning, Capel, Chapman Valley, Cockburn, Collie, Coorow, Corrigin, Cranbrook, Cunderdin, Dalwallinu, Dandaragan, Denmark, Dowerin, Dumbleyung, Esperance, Gnowangerup, Goomalling, Greater Geraldton, Kellerberrin, Kondinin, Kulin, Lake Grace, Mandurah, Manjimup, Melville, Mingenew, Moora, Mosman Park, Murray, Nannup, Narembeen, Narrogin, Nedlands, Northam, Perth, Pingelly, Plantagenet, Ravensthorpe, Rockingham, South Perth, Stirling, Swan, Tammin, Trayning, Victoria Plains, Vincent, Wagin, Wanneroo, West Arthur, Wickepin, Wongan-Ballidu, Woodanilling, York.

Management Notes (for the Swan NRM Region)

General Biology. Growth form. Grass. Life form. Annual, caespitose. Reproduction. Seed. Dispersal. Water, wind, mammals, combine harvesters. Photosynthetic Pathway. C3. Toxicity. Seed heads can become infected with fungal diseases and bacteria making this species toxic to stock. Pollen causes hay fever. Seedbank persistence. 2-4 years.

Notes. Naturalised in all Australian states. Found on a range of soil types from sandy loams to heavy clays. Hybridisation between Lolium species can make identification difficult. Has marginal to moderate salt tolerance, does not survive extended periods of waterlogging and is intolerant of shade. Allepothatic. Sets prolific seed. Seeds are dormant following dispersal for about 2 months, but this can vary greatly between cultivars and environmental conditions. Temperature and rainfall have a marked effect on germination. Herbicide resistance has been well documented.

Additional information. Origin. Mediterranean. History of use/introduction. Pasture. Similar exotic species. Lolium perenne, L. multiflorum.

Suggested method of management and control. Prevent seed set. Hand pull or spray with grass selective herbicide such as Fusilade® Forte in winter 4-6 weeks after opening rains. For larger plants up to flowering, increase rates of grass selective herbicide 3 to 4 fold. In agricultural areas, populations may be resistant to these herbicides and glyphosate may be needed. Spray 10 ml/10 L glyphosate when plants are vegetative up to when seed heads are emerging. Late season applications of herbicide can reduce the numbers of seeds produced, viablity and seedling fitness. 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         O Y Y Y Y Y Y Y  
Germination         O Y O            
Flowering Y               Y Y Y Y  
Fruiting Y Y               O Y Y  
Manual Removal             Y Y Y Y Y Y  
Herbicide Treatment O         Y Y Y Y Y O O  

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



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