Volunteers tame South Marlborough wilds

HAYLEY MCCAIRNS, South Marlborough Landscape Restoration Trust

In the remote high country of South Marlborough where rugged tussock landscapes meet alpine ridgelines, a dedicated group of volunteers is quietly taking on one of New Zealand’s most significant environmental challenges. The South Marlborough Landscape Restoration Trust (SMLRT) is leading the charge to restore and protect these iconic landscapes.

Since its establishment in 2016, SMLRT has worked across an 870,000-hectare area, stretching from the foothills south of Blenheim and the Wairau River to Molesworth Station near Hanmer. Its mission is clear: a backcountry free from wilding pines.

At the heart of this effort lies the Branch/Leatham, an expansive 52,000-hectare conservation area often described as one of the most complex wilding pine infestations in the country. Left unchecked, airborne seed from the Branch/Leatham could travel vast distances and infest more than 1 million hectares of vulnerable land. Ultimately, these wilding pines could reach from Molesworth to Kaikoura.

The work is physical, remote and relentless. Volunteers travel deep into the backcountry — often camping on site in the Lost Valley — to manually control invasive species like Contorta pine and Douglas fir.  Armed with drills, herbicide, and sheer determination they tackle trees spreading across riverbeds, ridgelines and fragile alpine ecosystems.

The Branch/Leatham catchment feeds into the Branch River, a key water source that ultimately flows into the Wairau River, supporting Marlborough’s communities and industries. Wilding pines threaten not only biodiversity but also reduce water yields (in some areas by 40 percent), impact land productivity and increase the risk of fire.

To date, the trust has helped control wilding pines across more than 130,000 hectares — a significant achievement in the face of a rapidly spreading threat. Yet, the work is far from over. Ongoing vigilance and sustained effort are critical.