Myrtle rust has now spread to Wellington, days after the fungal plant disease was found in Auckland for the first time.
The Ministry for Primary Industries' laboratory last night confirmed infections in three ramarama plants in a Hutt Valley garden.
The two-metre-high plants were in a row and heavily infected, myrtle rust response incident controller Catherine Duthie said.
Myrtle rust is a fungus that attacks and can seriously affect myrtle species plants including some significant natives such as pohutukawa, manuka, kanuka and rata.
It had previously been found in Taranaki, Te Puke, Waikato, Northland and, last month, Auckland.
"This new find, significantly further south of other known infection in the upper North Island, is very disappointing," Duthie said.
As with other positive finds, the trees are having their foliage sealed to prevent spore drift and are then being removed and deep buried.
"All efforts to date have been to contain infection where it is found," she said.
"However, we have been planning for the possibility that it turns out to be widespread and are realistic that it won't be feasible to keep removing all infected trees found long term.
"This new find will see us review our tactics and could signal a move to a longer-term approach to managing it in partnership with others, including local authorities, iwi and hapu, plant production industry, and interested individuals and groups.
"We'll be keeping people informed about any decisions and will provide the most up-to-date information about best practice in fighting this disease."
In the meantime, MPI encouraged everyone to keep an eye on myrtle species plants and report suspected myrtle rust disease to call MPI on 0800 80 99 66.
"So far ramarama and pohutukawa are the species we're finding most affected and these are the ones to look at carefully.
"If you think you've seen the distinctive yellow fungus, don't touch the plant or the rust, as this may spread it."