The humble pine is a hallmark of our Christmas landscape but experts are concerned its finding its way into places it shouldn't.
A new app has been launched to help people report any outbreaks of wayward Christmas trees and their relations to stop a mass outbreak.
Sherman Smith, wilding conifer manager for the Ministry of Primary Industries, says it’s easy to forget the trees are actually weeds.
"These things can spread a long way," he said.
It's estimated Wilding conifers have taken over close to 2 million hectares and wherever they spread, they overwhelm native plants and ruin the habitat for native animals.
They also suck valuable water out of catchments.
Land Information New Zealand created the app to help people report any pines found during their summer adventures.
"Outdoor users in particular are going to be going into remote places this summer… they're the people who will spot Wilding pines out in the areas we don't want them."
Wilding pine seeds can travel up to 20 kilometres, making the spread extremely hard to control. It's why even a single tree is worth reporting.
But it's not just pine - conifers include cedars, firs and spruces too.
Helen Payne from LINZ says she sees them everywhere.
"One tree can invade an entire landscape overtime so its important to see them and capture it.
"A few years later there'll be a few hundred trees and a few years after you'll have a few thousand trees. It happens slowly enough that you don't notice it but quickly enough that it becomes a big problem."