Pine alarm sounded 40 years ago

Scientists’ 1982 Warning Resurfaces Amid Concerns Over Government Conifer Planting Proposal.

Pines and tussock don’t mix.

A group of scientists from the Botany Division of the then-DSIR (Department of Scientific and Industrial Research) at Lincoln warned of the risks of conifers in New Zealand’s high country as far back as 1982.

But the recent government proposal to plant low-value conservation land—much of it in high country—does not appear to take into account the lessons of the past or the costly impact of wilding pine management in these areas, the Wilding Pine Network says.

“A recent timely find from one of our tireless campaigners, while cleaning out his mother’s treasures, was an article from May 1982 in The Press acknowledging the success of high-country forestry, but identifying that in some places these are a mixed blessing.”

Because of the demonstrated ability of exotic conifers to colonise New Zealand’s mountain lands—up to and beyond the limits of natural forests—the scientists warned of real danger to large areas of NZ’s landscapes and to some of the rarest native plants and plant communities.

“They acknowledged the value of conifers in commercial forestry but stated that there is strong evidence they have no place in mountain erosion control or in our mountain landscape, as they both impact our unique landscapes and threaten native plant communities.

“They stated that the evidence in support of tree plantings in eroded mountain land is fragile, and that there is no reliable evidence that any downstream benefits can be obtained from revegetation.

“They noted that the Crown has the major responsibility—most of the revegetation plantings have been made on Crown land under the control of the Department of Lands and Survey and the Forest Service.”

Particular concern was expressed about Pinus contorta plantings in places such as the Kaweka Ranges in the North Island:

“The widespread aerial seeding and planting of Pinus contorta makes it doubtful whether anything can now be done to prevent the species from becoming a permanent part of this mountain landscape,” the scientists wrote.

The head of the Waihopai Valley in Marlborough was also identified as a problem area, where seeding from pine plantations was invading a kanuka community considered important by botanists.

Another area of concern was the Patriarch Range, also in Marlborough, which marks the boundary between the distribution areas of a large number of native species. Large numbers of unique communities of smaller native plants had recolonised this area after it was burnt in ancient times.

“Pines and tussock don’t mix,” the Network says.

“We already have a massive challenge in the Mackenzie, which is wilding ground zero—where ecological and landscape values are derived from tussock.

“Let’s not exacerbate it.”

The Wilding Pine Network will hold its annual conference in Twizel later this year, from 14–16 October.