Biosecurity officers have asked a botanist in America to help identify a mystery plant found growing wild in Whangarei.
A Northland Regional Council staff member recently came across the sprawling vine in a council forest in Kamo.
Plant experts in New Zealand have identified it as a type of passionfruit, but not one they have seen before.
Council biosecurity manager Don McKenzie says the passiflora genus tends to choke other plant life and the council is very keen to stop the new plant spreading.
Mr McKenzie says the vine climbs into the forest canopy, and has bunches of small black fruit, that ripen even in winter.
At present, the vine is thriving in about 20 places in native bush behind Kamo and bird and rates may have spread it further already.
Mr McKenzie says the last thing Northland needs is another weed and the region's warm climate has already made pests of wild ginger, lantana and a host of other plants.