Mystery Whangarei plant identified

A United States-based expert has identified a mystery plant growing in forest near Whangarei as a passion flower native to Costa Rica and Panama.

However, while the Central American plant is apparently not a problem in other parts of the world, its invasive behaviour in Whangarei – where it was discovered for reportedly the first time in New Zealand recently – is worrying local biosecurity experts.

Don McKenzie, the Northland Regional Council’s Biosecurity Senior Programme Manager, says the plant has been identified by a Missouri-based expert in the United States as ‘Passiflora apetala’.

Mr McKenzie says initial indications are that the plant is largely restricted to a roughly four hectare area of Whangarei District Council-owned forest in the Kamo area where it has been growing high into the canopy of trees and smothering them.

How it came to reach Whangarei has not been established, however, one sample has now also been found in Kaitaia, apparently after being taken there in mulch from Whangarei.

“Unfortunately, it appears Whangarei may have just witnessed a regrettable world-first so far as this plant is concerned. It isn’t classed as a pest plant elsewhere in the world, but given the way it’s acting in the bush here - in particular its invasive sprawling and climbing behaviour - it’s a real worry for us.”

There are numerous examples around the world of plants which exist without causing problems in their natural habitats but become pests outside of them. One example most New Zealanders would be familiar with is gorse.

Mr McKenzie says MAF Biosecurity NZ has been made aware of the plant’s presence and will be working with the Council on the issue. At this stage Regional Council staff plan to destroy any of the plants they find in a bid to protect the environment.

 “We’re seeking the public’s help in this regard. We are keen to try to find out where it has come from and are asking people who encounter it anywhere, including their back yards, to contact us on (0800) 002 004.”

Mr McKenzie says Passiflora apetala is shade tolerant with glossy, bright green leaves similar in shape to a moth’s wings and with small, light-coloured flowers. It produces small black berries roughly the size of a grape which are inedible and non-poisonous.