Wild kiwifruit are beginning to emerge across the West Coast, with an infestation on the Karamea River and evidence it is now present throughout South Westland.
This was highlighted this week in a report before the Resource Management Committee of the West Coast Regional Council.
The report council has a renewed focus on biosecurity. Residents are being visited and offered advice around their obligations.
Vector Control Services operations manager Shanti Morgan told the Resource Management Committee on Tuesday this had included contacting Mawhera Incorporation about the pest plants emerging on its land holdings.
"We have not had a response yet," Morgan said.
Vector Control Services is owned by the regional council.
The report noted 40 pest plant inspections focused on pampas had been undertaken on individual properties in the past month.
"The owners/occupier of these properties have been issued inspection notices to destroy plants within a set timeframe."
Pampas compliance work was carried out in Okarito, Hokitika, the beach north of Cobden, in the lower Grey Valley, Coast Road, Cape Foulwind and at Karamea.
Three 'notices of direction' had been issued to landowners that had not destroyed pest plants within timeframes provided by council notice.
"Council have not proceeded with any fines against the Biosecurity Act or charge backs for compliance costs."
The biosecurity team had contacted the Buller, Grey and Westland district councils, and Kiwi Rail to advise them of their responsibilities under the Regional Pest Management Plan.
Morgan said one landowner had expressed concern at the cost of pampas control.
They were offered the option of managing flowerheads to reduce spread and given an option for an extended period of control. The pest plan did have provision to support landowners by providing control tools, including biological agents, or other methods such as herbicides.
In Buller two large infestations of wild kiwifruit along the Karamea River covering a hectare or more with 100 percent cover had been found.
An ecologist had also found a wild kiwifruit seedling near Lake Paringa, and alerted the council to several finds of small plants throughout South Westland over the past few years.
At this stage kiwifruit was not listed in the council's pest management plan. However, it was classified as an eradication species in neighbouring Tasman, and listed in other management plans nationally.
Councillor Peter Ewen asked if the outbreak of kiwifruit could be as simple as people throwing fruit out of the car window.
Morgan said wild kiwifruit can be bird dispersed.
Banana passionfruit was another pest emerging in the Karamea district.
Other invasions on the watchlist were spindleberry on the Orowaiti River at Westport, and vasey grass in Buller - the first identified population of the invasive weed in the South Island, and found by the Department of Conservation.
Additionally, DOC had identified red dragon knotweed in Buller, another new weed for the region. The department was aiming to eradicate both of those populations.
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