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Anthoxanthum odoratum L.
Sweet Vernal Grass

Sp.Pl. 1:28 (1753)
Conservation Code
Not threatened
Naturalised Status
Alien to Western Australia
Name Status

Tufted perennial, grass-like or herb, 0.1-0.8 m high (x 0.4 m wide). Fl. green-purple, Nov to Dec or Jan or Sep (occasionally). White sand, black sandy loam.

Amanda Spooner, Descriptive Catalogue, 24 August 1999


IBRA Regions
Jarrah Forest, Swan Coastal Plain, Warren.
IBRA Subregions
Northern Jarrah Forest, Perth, Southern Jarrah Forest, Warren.
IMCRA Regions
WA South Coast.
Local Government Areas (LGAs)
Albany, Augusta Margaret River, Bunbury, Busselton, Capel, Dardanup, Denmark, Harvey, Kalamunda, Manjimup, Plantagenet, Rockingham, Serpentine-Jarrahdale, Waroona.

Management Notes (for the Swan NRM Region)

General Biology. Growth form. Grass. Life form. Perennial, rhizomatous/caespitose. Reproduction. Seed. Dispersal. Water, wind, mammals (awns on fur), slashing, mixture with other grass fodder crops. Photosynthetic Pathway. C3. Toxicity. Can cause allergies to humans in the form of hay fever. Not directly toxic to animals, but indirect poisoning has been recorded when used in silage. Seedbank persistence. Short, up to 2 years. Fire response. Resprouts, increases in cover due to reduced competition.

Notes. Forms extensive ground cover and highly competitive with other grasses because of its rapid growth and early flowering. Produces prolific seed. Restricted to nutrient poor soils, especially those lacking phosphorous. Contains allelopathic chemicals that suppress growth of other plant species.

Additional information. Origin. Northern Africa, temperate Asia and Europe. History of use/introduction. Unknown, however it has been planted occasionally as an ornamental.

Suggested method of management and control. In small infestations hand remove plants ensuring rhizomes are removed. If all plant parts are not removed, hand removal as well as mowing can increase the number of infloresences and promote growth. Highly sensitive to glyphosate but in situations where selective control is needed, spray with grass selective herbicide in winter/spring. 2,2-DPA at 50 g/10 L + surfactant provides good control in spring when actively growing before appearance of seed head. Follow-up with seedling control. 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
Dormant     Y Y Y                
Active Growth           Y Y Y Y Y Y    
Germination         Y Y Y            
Flowering Y O             O Y Y Y  
Fruiting Y Y                      
Optimum Treatment           O O Y Y Y Y O Hand remove all year

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



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