By Roger MacRaild, VSTWP Extension Officer, 2014
The Meredith Dairy, run by the Cameron family, is located to the east of the Leigh River, within the area recognised as Victoria’s core infestation of serrated tussock. In 2009 the Camerons bought a neighbouring block as their business continued to grow. The site contained native values good enough to warrant a bush tender arrangement however the Camerons had a suspicion that some of the tussock grasses on the block were serrated tussock, a worrying prospect as it threatened both native diversity and production values.
Being an active land manager, Julie Cameron contacted the Victorian Serrated Tussock Working Party in 2013, and Extension Officer Roger MacRaild was able to visit the property and confirm their suspicions. From the location and size of the infestation it is thought that the serrated tussock was introduced to the site some years before, possibly from seed carried to the site on an excavator brought in to install access roads. The spread of the serrated tussock would have initially been slow as the area contained a good coverage of competitive pasture however an adjacent site was sprayed with herbicide, in preparation for tree planting, and the resulting bare ground facilitated a rapid growth of the infestation due to the lack of competition.
The infestation was treated in August 2013, plants scattered amongst the mostly introduced pasture grasses were spot sprayed with the selective herbicide Flupropanate, while plants located near waterways were treated with Glyphosate. The spot spraying of Flupropanate was selected in an attempt to minimise undesirable chemical impacts in a sensitive environment and also take advantage of the residual function of the herbicide. A reinspection of the site in October revealed a very good level of control with only two small plants found untreated, these were removed at the time of inspection.
Like most serrated tussock infestations this is a work in progress and for long-term success continued vigilance and follow-up treatment is essential, this is the case even when using residual herbicides as seed can remain viable in the soil far longer than a chemical’s residual effects.
With committed land managers like the Cameron’s this property has a good future, and their ongoing monitoring and treatment of serrated tussock will prevent any further spread and help to protect land owners further west in the state.