Banana passion vine retreats as community actions advance
Hobie Mercer’s rock-climbing skills have been necessary on some of the less accessible sites of banana passion vine infestation. Photo: Neil Wilson.
Banana passion vine is taking a hammering in Golden Bay. In the first year of a project in one part of the Bay alone, 7500 vines have been removed.
The highly invasive vine tries to take over the forest canopy, leading to the forest’s eventual collapse, according to Tasman District Council biodiversity officer Ken Wright.
“It’s a bad pest problem that has probably been here since the days of Pakeha settlement. It’s a requirement in Golden Bay for people to control it on their own properties under the Tasman Nelson District Regional Pest Management Strategy. It was introduced for its fruit, but there are alternatives that can be planted that aren’t so bad at spreading. Under the National Accord you’re unable to buy, sell, propagate or distribute the banana passion vine.”
Ken explains that the invasive vine can be quite daunting for landowners if they’ve got major infestations or if the vine is growing in places that are very hard to get to.
“It’s spread by birds and possums and the seeds can remain viable for up to five years. There are some areas of the Bay where the infestation is really bad, but action by community groups with a conservation ethic is starting to have a big impact.”
There are two main community groups combating the weed in areas with high biodiversity values, says Ken: Forest and Bird through its Weedbusters group, and a group that sprang up in Clifton through the efforts of Rocklands Road resident Chris Rowse.
Chris said that when he started cleaning up their property he discovered a lot of banana passion vine and one old man’s beard.
“We cleaned up a big gully relatively easily and then went back the next year and pulled out heaps of seedlings. Then there were a few the next year, but hardly any after that. I realised that the gully was just going to get reinfested by seed carried in by birds and possums, so I tried to activate as many people as possible to get involved in a community-wide programme.”
Chris knew of the existence of the Biodiversity Condition Fund, administered by DOC in Wellington. It is set up to help community groups with a common pest problem.
“They’ve got millions to distribute but a lot of projects to support in areas of great biodiversity value nationwide,” says Chris. “The whole bottom line is that they will only match what the residents themselves have spent in combating the pest. The landowners have to commit to maintaining the improvement too. The funding means that we can co-ordinate a programme and provide support to landowners, especially for the hard-to-get-to areas. The funding is for three years.”
Chris explains that every hour of effort the landowners put in themselves (or pay someone else to do) is used to calculate the funding the project attracts. The funding can then be used to pay specialist weed teams to go into difficult country where rock-climbing skills may be necessary or where the vegetation is so dense that the teams use a three-metre grid spacing while sweeping an area for weed vines. Wonga wonga, old man’s beard and scented jasmine are also on the hit list. Teams way-point each vine on their GPS and Nigel Mountfort at DOC uses that information to produce a map showing all the locations of the species being removed.
The Rocklands Road group has been co-ordinating the removal of banana passion vine from 13 upper-side properties, and is now in its second year.
“That means we’re mainly pulling out seedlings,” says Chris. “Next year we’ll go back to where we removed mature vines and pull out the seedlings that have sprung up there.”
Phase two of the project has taken in the lower side of Rocklands Road and beyond. It involves 31 properties and 1800 hectares of land in the area between Bird Road and the Rameka Creek. The project only applies to privately owned land.
Now Chris is talking about the beginning of phase three: Pohara, Pohara Valley and as far as the beginning of Ligar Bay. Landowners are in the process of being contacted, working bees have been arranged and data is being gathered.
“There’s no need for landowners to feel overwhelmed by the problem. The project will provide a management plan, including a map and an indication of what to do over the next few years. When it’s broken down into small steps it’s much more achievable,” says Chris. “If we all keep at it, the reseeding will be minimal.”
The eradication process is more complex than simple “slash and burn” says Chris.
“Vines are snipped off and painted with a 25 per cent Roundup solution. Vigilant gel is used sparingly and responsibly in some locations too.”
Chris says that the project is just part of a much bigger picture.
“There’s a lot of stuff happening all over Golden Bay. The Forest and Bird Weedbusters group have worked in quite a few sites and the backup provided by DOC and TDC means that we are systematically cleaning up Golden Bay. Ken Wright contacts the absentee landowners so they’re in the loop and their places are able to be included in the project. One overseas landowner organised a really good clean-up on his place. All that helps with the calculation of the funding.”
Anyone wanting advice on how to control weeds on their property can pick up information at the Takaka service centre or contact Ken Wright on 525 0020.
Neil Wilson
