Get on top of serrated tussock

Serrated tussock is commonly found in New South Wales and is considered a threat to farmers and landownersSerrated tussock alike. There is little to no nutritional value to livestock and it is a quick-spreading weed. Serrated tussock can significantly impact on native grasslands and greatly reduce feed quality.

Grazing trials in NSW have shown that sheep cannot live on a diet of mature serrated tussock. Early detection and intervention can greatly reduce the cost and effort of managing large infestations. Uncontrolled, serrated tussock can exponentially create a difficult and expensive issue for yourself and your neighbors. Serrated tussock seeds are largely spread by the wind. The more you have on your property, the more seeds are dispersed.

Bare ground and a lack of competitive pastures provide serrated tussock with the ideal opportunity to colonise. Maintaining vigorous, competitive pastures through fertiliser use and sound grazing management will help prevent serrated tussock invasion. Continual vigilance in controlling scattered plants is particularly important to keep the weed at a manageable level. Extra vigilance is required when droughts break and early control of seedlings is then vital.

Timing Development of seed head
Week 0 Seed heads first appear as thick tillers in early to mid spring.
Week 2 Seed heads begin to emerge from these tillers.
Week 3 Most seed heads have fully emerged and opened, and have a purple tinge.
Week 5 Seeds reach the milky dough stage.
Week 6 Seeds reach the dough stage.
Week 10 Seed heads are fully developed and ‘weep’ over the tussock to the ground.
When mature they break off at the base and are spread by wind.


Controlling Serrated Tussock

There are many ways to control serrated tussock in the different stages of growth. Other than good pasture management, using chemical herbicides will get you a quick win.

Flupropanate herbicides

Flupropanate is a selective herbicide which is perfect for selectively treating serrated tussock. It can remain in the soil for up to two years. Flupropanate can take months to kill serrated tussock, requiring a mixture of glyphosate and Flupropanate to stop seed production.

Glyphosate herbicides

Glyphosate herbicides are non-selective and are available under a range of product names. The main applications of glyphosate herbicides in a serrated tussock control program include an application in spring in preparation for crop or pasture establishment in the following autumn; and carefully timed applications that use the herbicide selectively to preserve existing desirable pastures and prevent serrated tussock from seeding.

Spot spraying

Spot spraying using flupropanate or glyphosate herbicides can be used to control individual tussocks or small patches on all types of terrain. Spot spraying can be undertaken throughout the year when conditions are favourable, however; it is essential to spray before plants set seed (seedlings can set seed at 18 months of age). Both flopropanate and glyphosate herbicides can damage desirable pasture species hence care must be taken to apply herbicide only to the tussock plants.

A spray shield can be fitted to a handgun to minimise off-target damage. Make sure spot spraying equipment is calibrated to ensure the correct rate of herbicide is applied. A coloured dye can be added to the herbicide to indicate which plants have been sprayed. It will still be necessary to reinspect spot sprayed paddocks to check for seedling tussocks or smaller plants that may have been missed.

Broadacre spraying

Herbicides can be applied using a boomspray. Flupropanate is appropriate for boom spraying and has less potential for non-target damage (particularly to trees) than glyphosate.

We stock a wide range of weed sprayers and agricultural vehicles to assist with the right solution for you.