Wilding Pines

What grasshopper?

What is perhaps less well known are the numbers of endangered plant and insect species in this area, including a tiny, silvery grasshopper, dating back 100 million years, which will be wiped out if wilding pines continue their rampage across their territory.

In the past, help in controlling the spread of these wilding pines has come from the Department of Conservation (DoC) and regular ECan-organised wilding pine destruction days – dubbed “No Green Needles” days - with volunteer help from tramping and four-wheel drive club members.

But a new Waimakariri Alliance group has now been formed with the bold goal of raising $1 million to make serious inroads in controlling wilding pine spread and saving the native plants and grasshoppers.

The grasshopper - Brachaspis “Broad Stream”, was first described in 2004 by entomologist Simon Morris. “This strange, grey-camouflaged grasshopper occurs only along a 200 metre stretch of the riverbed between two rock bluffs in mid-Broad Stream,” says Gerry McSweeney, co-owner of Wilderness Lodge.

Less than 2cm long, it is related to the endangered grasshopper (Brachaspis robustus), found only in the Mackenzie Basin. These insects, closely related to the New Zealand alpine grasshoppers, are thought to have changed little in 100 million years.

What is the Waimakariri Alliance?

The newly formed Waimakariri Ecological Landscape Restoration Alliance brings together more than 20 groups from local, regional, and central government, runholders, tourism interests, ski field operators, Transit NZ, Transpower, Orion, DOC and environmental groups.

“If we don’t make serious progress in the next few years it will be unaffordable to stop the pines spreading over the whole basin, right over to the Torlesse Range,” says David Hewson, senior resource care officer at Environment Canterbury.

The plan is to raise about $1million over the next eight years to remove the existing wildings, with a recently-completed report, highlighting the urgent areas.

DoC is also working hard on the problem, with the aim of protecting the Korowai/Torlesse Tussockland Park, downwind of the spread.

“Although ECan’s volunteer wilding-out efforts have brought the spread back 4km, we are now we are into the dense reseeding areas and need a bigger push to have an effect,” says David.
Fortunately conifer seeds only stay viable in the soil for a short time (three to five years), which means if you keep the area clear for that time and remove the source, you control it. This year, volunteers will concentrate on the Cave Stream area, where the Narnia film was made, and on containing the easterly spread below Constitution Hill.
Despite the enormity of the problem ahead of them, volunteers have cleared wildings from Porters Pass to Lake Lyndon, Mt Cheeseman and Porter Heights skifields, Lake Pearson fan and Corner Creek.

Wilderness Lodge and Flock Hill Station fight back

The 100 hectare Dracophyllum Flat above Craigieburn Cutting has been kept free of pines by guests from Wilderness Lodge. Every year, for the last 10 years, about 60 groups of eco-tourists comb the flat and pull thousands of seedlings, complementing DoC work.

“People think it looks rubbish,” Gerry McSweeney says, “But we’ve got an amazing variety of native plants, including sub-alpines growing on the frost flats right beside the road.  There are four species of dragon’s tooth, three species of hebes, two mountain daisy species, and native orchids – onion, sun, and leak orchids.” There are also grassland gentians and an unusual narrow-leaved snow tussock normally found on high mountain slopes.  “If you let it go, all this would be smothered,” says Gerry.

The bed of Broad Stream near Wilderness Lodge, is a deceptive place – a tumble of grey rocks in a small braided river bed, with clumps of tutu, low-growing willow herb, and mat daisies.
Few people would spot the rare dinosaur-aged grasshopper which lives there. The stream bed is also home to three species of endangered plants - Kirk’s broom, Waimakariri Helichrysum, and Wall’s Coprosma - “a biological treasure trove,” says Gerry McSweeney.

Richard Hill, who leases Flock Hill Station, has dealt to the heavy infestation of wilding pines on his roadside flats by mulch-mowing them.  Above his mulched paddocks there are many seeding trees on exposed ridges poised to send clouds of pine seeds into Korowai/Torlesse Tussockland Park.  Funding from ECan’s Regional Pest Management strategy means contractors will remove these high risk trees before winter.

How can I help the Waimakariri Alliance?

To find out how you can contribute to the Waimakariri Alliance with funds or volunteer work, please contact David Hewson at Environment Canterbury : 03 363 9336 or email david.hewson@ecan.govt.nz