Wilding pines battle ramps up in Marlborough

8:19 pm on 23 October 2020

In the palm of Jaquetta Bradshaw's hand is a sapling with the power to dry rivers, start bush fires and kill off native life.

South Marlborough Landscape Restoration Trust co-ordinator Jaquetta Bradshaw with a wilding pine sapling.

South Marlborough Landscape Restoration Trust co-ordinator Jaquetta Bradshaw with a wilding pine sapling. Photo: Chloe Ranford / LDR

It's a wilding pine. The same tree that helped spread fires at Lake Ōhau village and Lake Pukaki in the last two months.

With their quick and dense growth, wilding pines aggressively outcompete New Zealand natives and habitats, turning Marlborough's mountain tops from gold to green.

The sapling's "mother tree" - now dead - likely sailed 10km on the wind from Black Birch Reserve as a seed.

Some seeds germinate as far as 50km from their parents.

If the South Marlborough Landscape Restoration Trust gets its way, that would no longer be the case. The trust, where Bradshaw is co-ordinator, received government funding last month to continue its battle against wilding pines, including $115,000 for The Ned, near Blenheim.

Wilding pines that have escaped from a harvested plantation.

Wilding pines that have escaped from a harvested plantation. Photo: Chloe Ranford / LDR

It also won $86,700 from the Department of Conservation (DOC) in August to control pines in the Ferny Gair/Black Birch area, by The Ned. This was being added to funds from Yealands Estate, as the area feeds drinking water to Seddon.

During a helicopter flight over the area, Bradshaw explained the threat. "People think mountain plants are hardy, but mountains are very fragile environments. Plants are slow to grow here, so when conifers come, they win."

The trust looks after 10 management areas in South Marlborough, each with its own pine control programme, covering about 870,000ha of "steep, dry and high" farm land.

Terrain was so difficult to access that experienced pest controllers like Andrew Withers had to be flown in.

Once there, Withers and his team would have to trim back wilding pines with chainsaws, drill holes in the trunks and inject them with herbicide, and pull saplings out by hand.

"We can also boom spray trees, which is when poison is sprayed from a line of nozzles out of a helicopter," he said.

A pest controller drills holes in a pine before injecting it with poison.

A pest controller drills holes in a pine before injecting it with poison. Photo: Chloe Ranford / LDR

Cutting down a tree is not enough. The fallen pine could still produce seeds and would prevent stock from grazing. The trust has cleaned up over 80,000ha to date with the help of landowners and the Lotteries Commission.

Work on The Ned, a 20,000ha area, will begin next month.

Over the mountains, in the Molesworth Station, the trust is working with the Marlborough District Council and other stakeholders to protect the 180,800ha farm from the pines - a project that received a $3.04 million windfall last month.

The trust aims to reduce wilding pine numbers in South Marlborough by 2030, in line with national objectives. It needs $100,000 alone to finish the Awatere area, where Bradshaw found the sapling in her hands.

Some pines in the Awatere had escaped from plantations, but in the Branch/Leatham, Molesworth and Waihopai Valley areas wilding pines were planted in the 1950s and 1960s to prevent erosion.

Checking out the Awatere area are, from left, trustee Stuart Dudley, councillor Barbara Faulls, trust co-ordinator Jaquetta Bradshaw, pest controller Andrew Withers, trust chair John Oswald, Marlborough Helicopter pilot Simon Moar, and trustee Ross Beech.

Checking out the Awatere area are, from left, trustee Stuart Dudley, councillor Barbara Faulls, trust co-ordinator Jaquetta Bradshaw, pest controller Andrew Withers, trust chair John Oswald, Marlborough Helicopter pilot Simon Moar, and trustee Ross Beech. Photo: Chloe Ranford / LDR

The Branch/Leatham - which feeds water into the Wairau River and therefore local vineyards - has one of the worst pine infestations in New Zealand, and is next on the trust's to-do list.

Trust chair and vineyard owner John Oswald said the pines were "thirsty" and could dry up downstream waterways. Fires fed by the pines could also taint grapes with smoke.

Trust chair John Oswald holds a small wilding pine.

Trust chair John Oswald holds a small wilding pine. Photo: Chloe Ranford / LDR

Hours after visiting the Awatere area, Bradshaw and Oswald petitioned the Nelson Marlborough Conservation Board for funding.

"The Branch/Leatham is out of sight, out of mind, so everyone says to leave it alone. But it's a major seed source."

Left unchecked, wilding pines would spread to another 7.5 million hectares of land, costing $4.6 billion over 50 years.

The Marlborough Sounds Restoration Trust was awarded $355,000 by the government last month to continue its "successful" pine programme, in its 12th year.

Trust co-ordinator Siobhan Browning said the funding would help it "bite off a bigger mouthful" of wilding pine control this year.

 The Awatere Valley is one of 10 management units looked after by the South Marlborough Landscape Restoration Trust.

The Awatere Valley is one of 10 management units looked after by the South Marlborough Landscape Restoration Trust. Photo: Chloe Ranford / LDR

The trust had already killed off pines on D'Urville Island and the outer Pelorus Sound, with the help of DOC, landowners, businesses and the council.

Marlborough Mayor John Leggett said in a statement last month that the funding was a "huge win" for biodiversity.

"There's a perception out there that all trees are good, but unfortunately wilding pines are not," he said.

The council last year amended its regional pest management plan, adopted in 2018, to include a new pest pine programme which would kick-start a "regional framework" and support the national pine programme.

People wanting to volunteer for the South Marlborough Landscape Restoration Trust can email info@marlboroughrestoration.org.nz.

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