Serrated tussock is a weed of national significance. Highly adapted to a range of environments, it seeds prolifically and is difficult to control. The wind spreads large volumes of seed across long distances, allowing new populations to establish over large areas.
Jonathan Lawson, Regional Weeds Coordinator at Northern Tablelands Local Land Services, cautions against the threat and is keen to emphasise the serious risk it presents to the Northern Tablelands grazing system.
“Serrated tussock is one of the world’s worst weeds. By far, it is the most destructive grassland weed species and most dangerous risk that landholders will encounter,” Mr Lawson said.
While the weed has been detected in the Northern Tablelands for some time, according to Mr Lawson it is gradually spreading.
“As weed officers are conducting property inspections across the region, sightings of serrated tussock are becoming more common which is very alarming. It poses a serious threat to farm management systems,” he said.
Difficulty in controlling the weed is attributed to a number of factors. It is unpalatable to stock, is easily spread long distances and has a long seed life. Hay and grain can be contaminated by it and seed can be readily transported to unaffected areas by slashers, vehicles and tractors.
Serrated tussock is a notifiable weed under the Biosecurity Act. Once identified, landholders are obliged to report it to local weed officers.
“Northern Tablelands Local Land Services are very keen to work in conjunction with landholders to determine the most effective treatment through a management program. Once established, it can take up to twenty-five years to eradicate under a managed control program,” Mr Lawson said.
In times of drought, serrated tussock spreads due to the lack of competition. The soil may be more open due to the lack of ground cover. As the seed is spread in the wind, it may be easier for the plant to establish in dry conditions.
On the flip side, it is also under drought conditions that the weed is more likely to stand out and be easier to identify. Northern Tablelands Local Land Service will be conducting serrated tussock identification and management workshops in the coming months as not all landholders are familiar with the weed. Light green in colour, serrated tussock is a perennial grass approximately 50cm tall with fine and tightly rolled leaves. In winter it becomes bleached and straw-coloured. The leaves feel serrated when run through the fingers, giving the weed its name.
Landholders concerned about potential infestation are advised to contact Northern Tablelands LLS on 0429 914 207.