The first confirmed case of the deadly tree fungus myrtle rust has been found in Wellington.
It was discovered on a ramarama tree near the Zealandia ecosanctuary in Highbury late last week.
The discovery has kicked off an investigation from the Ministry for Primary Industries, as well as a Wellington City Council appeal for the public to be vigilant in looking for any more suspected cases.
Wellington City Council environment partnership leader Tim Park said an incursion was inevitable, but could be managed better if locals helped by reporting suspected infections.
"We have many trees in Wellington, such as pohutukawa and rata, that could be seriously impacted by the fungus.
"As a worst-case long-term scenario, a serious infestation could change the face of pohutukawa-rich suburbs like Seatoun and Island Bay.
"If you think you have seen myrtle rust, please take a photo, while taking great care not to touch the plant, and contact the Ministry for Primary Industries on 0800 80 99 66.
"When it comes to myrtle rust infections, ramarama are like the canary in the goldmine, so people should keep a close eye on them in particular."
Zealandia has put in place surveillance to detect any myrtle rust infections that come inside its fences.
Zealandia conservation and research manager Dr Danielle Shanahan said myrtle rust was a big concern for them.
"We are undertaking careful surveillance in the sanctuary to ensure organisations such as the ministry for Primary Industries and the Department of Conservation have the best information to map myrtle rust's spread, and to identify ways to look after affected species."
Wellington City Council and Zealandia have teamed up to protect local vulnerable species, including Bartlett's rata and swamp maire.
Other vulnerable but non-native species include lilly pilly, gum trees, bottle brushes and feijoa.
The Highbury infection is the first report of myrtle rust in the Wellington City area.
However, there are 30 known infestations in the Wellington region, most of them in the Hutt Valley.