The public is being asked to be vigilant after a second discovery of seedlings of the highly invasive vine bat-wing passion flower (Passiflora apetala) at ‘the Nook’, in the Whangarei Heads area.

Joanna Barr, the Northland Regional Council’s Biosecurity Manager - Pest Plants, says the species is not yet widespread in Northland and is part of an eradication programme.

Spread by birds, the extremely fast-growing invasive species can go from seed to fruiting adult within 8 months. Its shade tolerant seedlings can establish in the bush and then climb to smother the canopy.

The plant was discovered by local volunteer Eileen Alexander on her property - one 20cm seedling along with two more tiny ones - that look to have come from birds perching in the puriri trees above.

The first discovery in the Nook area was also made by Ms Alexander when volunteering at the local nursery on a neighbouring property in January last year.

Ms Barr says following that discovery, a subsequent survey, door-knocking, Facebook campaign and mail drop all failed to locate a source plant or any further infestations.

She says both discoveries found to date have been small seedlings that look to have been early establishment from birds. "Given both discoveries were relatively close to one another it suggests the source plant must be too."

Ms Barr says 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."

The adult foliage is quite distinctive - with a wing-like two-lobed leaf that gives it the name ‘bat-wing’, that often have a light-coloured stripe down the middle of each ‘wing’.

"The juvenile foliage is a bit different - 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."

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