Myrtle rust disease continues to spread

MPI staff at Kerikeri Plant Production, where the disease was first detected on May 2. Photo / Peter de Graaf

A plant disease first discovered in Northland has now been found in the Bay of Plenty for the first time.

Myrtle rust, which attacks trees such as pohutukawa, manuka, feijoa and eucalypts, made its first appearance on the New Zealand mainland at a Kerikeri plant nursery in early May.

While its spread in Northland appears to have been contained - the number of infected properties remains at four - it has now been identified at 39 properties in Taranaki including plant nurseries, gardens, an orchard and a golf course.

Yesterday tests confirmed its presence in the Bay of Plenty, after a Te Puke woman called the Ministry for Primary Industries about suspicious symptoms on a mature ramarama tree in her garden.

MPI myrtle rust response incident controller David Yard said the new find, the first in weeks outside the key infection area in Taranaki, was "very disappointing".

"We had thought that the incursion could be contained to the small geographical area around Waitara. While it's too early to say what the new detection will mean in terms of the ongoing operation, it's certainly not good news in terms of its distribution in New Zealand."

Movement of plant material or other risk materials from the property had been banned. MPI staff were removing the tree, spraying the area with fungicide and inspecting neighbouring properties.

Preliminary talks with the property owner had not found no obvious link with the situation in Taranaki or Northland, and she had not bought any new plants from nurseries recently.
That suggested the latest case of myrtle rust was a wind-borne infection.

Mr Yard thanked the Te Puke home owner for contacting MPI as soon as she saw signs of the disease.

"The public response to myrtle rust has been huge and gratifying. So far we've had 822 calls reporting suspected myrtle rust. It's vital information. Building our knowledge of this issue and the distribution of the disease will enable us to make the best possible decisions about managing this into the future."

Meanwhile, the nursery where the fungus was first detected, Kerikeri Plant Production, was cleared to re-open for business on May 29.

Nationally the number of affected properties is now 46. Go to www.mpi.govt.nz/myrtlerust for more information or call 0800 80 99 66 if you think your plans are infected.