What chemicals are registered for serrated tussock control?

Herbicides

Herbicides are extremely beneficial in controlling serrated tussock but should not be relied on as a sole means of control.  "When a landholder relies on herbicide alone, their serrated tussock programs typically fail - the weed re-establishes from seed in the soil, or blows in." 

Integrated weed management, using a variety of methods, is critical for the successful long term control of serrated tussock.

A number of herbicides are registered for use on serrated tussock in Australia.  To be effective these herbicides must be applied at the right time and with correct application rates and this will vary depending on the situation and density of serrated tussock.

Always carefully read and follow all label directions, material safely data sheets, and any off-label minor permits.  And remember, you are required to have Chemcert Accreditation to apply herbicides in Australia.

Herbicide resistance is a real issue with a number of confirmed instances of serrated tussock propulations resistant to flupropanate in NSW and Victoria.

Herbicides currently registered for use on serrated tussock

Glyphosate is a broad spectrum systemic herbicide used to kill weeds, especially annual broadleafed weeds and grasses.  Glyphosate is absorbed through foliage and translocated to growing points.  Because of this mode of action it is only effective on actively growing plants.  Glyphosate is marketed around the world in different solution strengths under many tradenames.  Glyphosate is effective in killing a wide variety of plants including grasses, broad leaf and woody plants.  Care must be taken to ensure off target damage is limited.

Flupropanate is a selective herbicide used to kill certain perennial grass weeds including serrated tussock in agricultural situations.  Flupropanate is slowly absorbed by the root system of plants and may take 3 - 12 months depending on weather conditions and plant growth.  Flupropanate will selectively kill certain plants while others are reasonably tolerant.  Residue in the soil may suppress weeds and other susceptible species for one or two years.  Supression of seed set is only successful if application is made serveral months before seed set.  Flupropanate is marketed in Australia under several tradenames and in liquid and granular form.  Care must be taken to ensure off target damage is limited.

2,2-DPA is registered for control of serrated tussock but does considerably more damage to desirable species than flupropanate.  It is a less often used chemical.