Next step in control of Chilean Needle Grass imminent

Environment Canterbury’s Biosecurity Section is preparing to control approximately 200 hectares of Chilean Needle Grass on three North Canterbury properties in the coming weeks.

Chilean Needle Grass infests over 3,000 hectares of land in Marlborough, Hawkes Bay, and since November 2008, Canterbury. Initially Chilean Needle Grass was found at Spotswood, near Cheviot on a vineyard and four adjoining properties.

Until October last year there was no effective tool available to combat this plant pest.

Environment Canterbury’s Principal Biosecurity Advisor Laurence Smith says Environment Canterbury has supported Marlborough District Councils application to registering of Taskforce herbicide (active ingredient flupropanate) in New Zealand.

“Taskforce is a slow acting root absorbed herbicide that is reputed to specifically control Chilean Needle Grass while leaving most other plant species relatively unscathed when it is applied at label rates.

“Initially Taskforce was registered for ground application only, however more recently Environment Canterbury submitted to the Environmental Protection Agency in support of an application from Marlborough District Council to allow taskforce herbicide to be applied from the air,” says Mr Smith.

In December 2011, Chilean Needle Grass was found growing on a beef and sheep hill country property near Waiau. Due to the topography and size of the infestation, aerial application of Taskforce was the only method of control that was considered effective. There are now nine properties known to be affected by Chilean Needle Grass in Canterbury.

Taskforce aerial application was approved by the Environmental Protection Agency at the end of June 2012. There is 280 hectares of land currently affected by Chilean Needle Grass in Canterbury; most of the dense infestations will be controlled in the next few weeks to prevent seeding in November. A residual herbicide, Taskforce may provide up to 5 years of control.

“Environment Canterbury is also planning the other components of this seasons Chilean Needle Grass programme. These work streams include community involvement, a public awareness programme, containment protocols at existing sites, surveillance and searching,” says Mr Smith.

Originating in South America and closely related to Nassella tussock, Chilean Needle Grass is capable of invading much of Canterbury’s dry hill country. It threatens sheep farming viability with its sharp needle like seed head causing wool, meat and pelt damage as well as animal welfare issues.

The aerial application of Taskforce in this area, is a one off application to control a significant outbreak, the responsibility of controlling the plant pest otherwise sits with the land occupier. If you think your property has Chilean Needle Grass on it, please contact our Biosecurity section and we can help.