An outbreak of myrtle rust in a number of council gardens has prompted the removal of a hedge on Tongariro Domain near the rose garden.
Myrtle rust is a fungal disease affecting plants of the myrtle family, including natives pōhutukawa, mānuka, rata and in this case, lophomyrtus red dragon. It has microscopic spores that spread easily by wind, or via insects, birds, people or machinery. The Ministry of Primary Industries states it is likely it arrived in New Zealand on strong winds from Australia’s east coast, where myrtle rust is widespread. It caused leaves to appear rusty and curl up before eventually killing the host plant.
Parks manager of sport and horticulture Andrew Moor said there had been several reported cases of myrtle rust in the Taupō District since April 2017, but this was the first in major council amenity gardens.
“This hedge is in one of our most valued botanical assets, the rose garden and wider Garden of Significance which is of real concern,” he said. “We have had to remove the affected hedge and are working to remove other affected plants in town.”
He said the Garden of Significance contains several large natives that can be susceptible to myrtle rust and these include northern and southern rata.
“We want to protect our botanical collections, minimise myrtle rust in our district and reduce the risk of it spreading to nearby susceptible plants,” Mr Moor said.
He said the hedge could be easily replaced and was not high value, but the rust was unattractive and it detracted from the setting of the rose garden.
There were instances of myrtle rust in town streetscapes on Tūwharetoa Street, and several other locations that would also be either contained and monitored or removed, he said. All of the affected plants in council gardens so far had been the lophomyrtus red dragon.
To help prevent the spread of myrtle rust you can access Ministry of Primary Industry guidelines and download a pdf file on how to remove infected plants on the Biosecurity New Zealand website.
The horticultural team remove a hedge plant affected by myrtle rust alongside the rose garden.