Central Otago Wilding Conifer Control Group (CWG) project manager Pete Oswald said the immediate indications after the trial recently showed controlled burns could be a useful tool for controlling wilding pines in specific circumstances.
Some of the circumstances included, tree size, density and consistency, ideal fuel and weather conditions leading up to the day of and after the burn as well as the considerable time investment and long-term planning from landowners.
Despite the early results, the burn required conditions rare in Central Otago and the work before, during and after the controlled burn made it an expensive and time-consuming process, he said.
The trial was held on a private farm and was a collaboration between neighbouring commercial forests, farmers and CWG.
Crown Research Institute Scion were also present to research the effectiveness of the fire by measuring equipment deployed in the burn area by CWG and observations by Scion staff.
"If it is as successful as early assessments indicate, this has greatly progressed CWG’s control programme in this area towards protection of the surrounding land including over 50,000ha of conservation land," Mr Oswald said.
The controlled burn went as planned, but the true success of the fire would not be knowing until at least the next growing season, he said.
Biosecurity New Zealand director pest management John Walsh said the iconic Central Otago landscapes of golden tussock, grasslands and shrublands were highly vulnerable to wilding pine invasion.
If wildings were not controlled, large areas of the region would be impacted as they reduced land available for grazing, limiting future land use due to the cost of removal, he said.
As Central Otago was the driest region in the country, dense wilding conifer infestations reduced water yields impacting water availability and aquatic ecosystems.
Wilding conifers also provided fuel to wildfires, increasing their intensity, he said.
Controlled burning was one of the many tools available to manage wilding pine populations.
The National Wilding Conifer Control Programme would use the information gathered from the trial to understand which situations and conditions best suited the use of fire as a tool.
The information could then be shared with land managers so they could undertake the control method as effectively and safely as possible, he said.
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