Eileen Alexander with the young bat-wing passion flower found on her Whangārei Heads property. Photo / Supplied
Eileen Alexander with the young bat-wing passion flower found on her Whangārei Heads property. Photo / Supplied
A highly invasive pest vine that can smother, shade and strangle vegetation has been found for a second time in Whangārei, prompting Northland Regional Council to ask the public for help finding it.
The public is being asked to be vigilant after a second discovery of seedlings of the highly invasive bat-wing passion flower (Passiflora apetala) vine at 'the Nook', in the Whangārei Heads area.
Joanna Barr, NRC's biosecurity manager - pest plants, said the species is not yet widespread in Northland and is the subject of an eradication programme.
Barr said it is spread by birds and the extremely fast growing invasive species can go from seed to a fruiting adult within eight months.
It's shade tolerant seedlings can establish in the bush and then climb to smother the canopy.
A 20cm seedling and two smaller specimens were discovered by Whangārei Heads volunteer Eileen Alexander on her property. The plants looks to have come from birds perching in puriri trees.
Adult bat-wing passion foliage is quite distinctive with a wing-like, two-lobed leaf that gives it the name. These often have a light-coloured stripe down the middle of each 'wing'. Photo / Supplied
The first discovery in the Nook area was also made by Alexander when volunteering at the local nursery on a neighbouring property in January last year.
Barr said after that discovery, a subsequent survey, door-knocking, Facebook campaign and mail drop all failed to locate a source plant or any further infestations.
She said both discoveries found to date have been small seedlings that look to have been established through birds.
"Given both discoveries were relatively close to one another it suggests the source plant must be (nearby) too," Barr said.
The species is a major threat to the regionally significant Manaia Ecological District.
"We need all residents on the lookout for this species and to report anything they think could be bat-wing. The sooner we find the source, the better chance we have of locally eradicating it,'' she said.
The adult foliage is quite distinctive - with a wing-like two-lobed leaf that gives it the name 'bat-wing' - and often have a light-coloured stripe down the middle of each 'wing'.
"The juvenile foliage is a bit different - (it) looks a bit like little ducks' feet. The vines produce small black berries the size of a small grape, which are inedible to humans but are very attractive to birds."
Anybody who spots the plant can report it to NRC Environmental Hotline 0800 504639 or email info@nrc.govt.nz.
The bat-wing passion flower's distinctive flower. Photo / Supplied
Bat-wing passion flower facts:
Bat-wing passion flower is an invasive, shade-tolerant vine. It has distinctive wing-like shaped leaves that may have a pale green stripe along the midrib, or it can be plain dark green. It often has a sheen to it (particularly with maturing juveniles and adult plants). Younger plants have less sheen.
Bat-wing has small yellow or light-green coloured flowers (7-12mm diameter) which are without petals. It produces small berries (7-15mm in diameter), which start out green and mature to black.
As bat-wing is shade-tolerant, it can grow in a range of locations. It has been found in regenerating native forest and scrub, home gardens and among hedges and fence lines.
Why is it a problem?
Bat-wing can grow high into the canopy of tall trees. It has the ability to smother, shade and strangle the vegetation it grows on.
Bat-wing also produces large numbers of fruit, with each fruit containing about 20 seeds. Even unripe fruit can produce viable seeds. Many hundreds of seedlings have been found under some plants. It can also grow from stems that touch the ground or from plant fragments.
