February 24, 2026

#regional: South Marlborough Trust Takes on South Island’s Worst Man-made Environmental Disaster

Matthew Tukaki Posted On February 24, 2026

A local environmental group is ramping up efforts to address what it and others describe as the South Island’s worst man-made environmental disaster – the spread of invasive wilding conifer trees that are threatening vast swathes of high country landscapes.

The South Marlborough Landscape Restoration Trust, established a decade ago, has been working to combat the unchecked proliferation of wilding pines across the Awatere Valley, Branch and Leatham catchments and surrounding areas. These non-native trees, originally planted for erosion control, have spread rapidly over hundreds of thousands of hectares, altering ecosystems, degrading farmland and consuming precious water resources.

Landowners, conservationists and rural communities have been calling for urgent action as the pines encroach on native grasslands, choke waterways and threaten biodiversity. Seeds from the trees travel long distances on the wind, making containment a difficult and costly task that has frustrated both volunteers and government agencies.

Trust members and supporters argue that without significant investment in landscape-scale control, the wilding pine problem could become irreversible. Dense infestations already make some valleys almost impenetrable, and there are fears that if left unchecked, the trees could dominate habitats once cherished for their native flora and fauna.

Those working on the ground say the ecological impacts extend far beyond lost native plants. Wilding pines are deep-rooted and thirsty, reducing water flows that are crucial for both local agriculture – including viticulture – and maintaining healthy river systems. Reduced water availability has implications for rural economies and the long-term resilience of communities that depend on these landscapes.

The Trust has been engaging with government ministers, scientists and biosecurity officials to highlight the scale of the challenge and press for expanded funding and coordinated control programmes. While some civil defence and biosecurity funding exists under national wilding conifer control efforts, advocates say it falls short of what’s required to address the hardest-hit catchments.

Restoration work involves manual removal, targeted spraying, aerial control and replanting with native species, but volunteers and coordinators consistently stress that effort must be matched by long-term resourcing and policy support. They contend that a piecemeal approach will not halt the march of the pines unless funding, strategic planning and rapid action are significantly stepped up.

The push to protect and restore these landscapes is part of a broader debate around biosecurity and invasive species management in Aotearoa. With climate change and shifting land use patterns complicating the ecological picture, experts say strong partnerships between communities, councils, iwi and central government will be essential to meet restoration goals.

As awareness of the wilding pine crisis grows, so too does the call for urgent national support. For the South Marlborough Landscape Restoration Trust and the communities it represents, the message is clear: tackle the disaster now, or risk losing these landscapes forever.