The Ministry for Primary Industries (MPI) and Department of Conservation (DOC) are stepping up the fight against myrtle rust with the introduction today of legal restrictions on the movement of myrtle species plants and green waste out of an area of the Taranaki region.
MPI's Myrtle Rust Response Incident Controller David Yard says to help control any spread of myrtle rust from the most infected area around Waitara, MPI has imposed a Controlled Area extending 10km out from the known infected properties.
"It is illegal to move any plants or trees belonging to the myrtle family and any garden waste, fruit (feijoa or guava) or prunings from those plants out of this area."
Mr Yard says during the cold winter months, myrtle rust symptoms are suppressed and it's proving difficult to get a good measure of exactly where the disease is present and the scale of the outbreak.
"We could be dealing with an extensive outbreak, but there remains some possibility we may only have a small level of infection that could ultimately be eradicated.
"Until the weather warms up and any infection present becomes much more visible, we need to do everything possible to contain and destroy it in the areas we know about.
"Come spring, if we find it is limited to the current known areas, we'll have the best possible chance to get rid of it from New Zealand," Mr Yard says.
Myrtle rust affects only plants in the myrtle family which includes pōhutukawa, mānuka, rata, ramarama, Lilly Pilly, eucalyptus (gum trees) and feijoa.
"We encourage Taranaki residents to support us in this important job by not moving myrtle species plants, fruit or myrtle green waste out of the specified Controlled Area. Garden waste should be disposed of responsibly within the Controlled Area – for example at the Waitara transfer station or the New Plymouth landfill. Myrtle family plants can still be bought and planted within the zone."
Taranaki is the focus of the effort, even though myrtle rust has been found in other regions. Two small Northland and Te Kuiti infections have been managed and there has been no further sign of the disease in those areas.
The rust has also been found on a small number of properties in Te Puke in the Bay of Plenty and work is still underway to determine the scale of the situation there.
There are no restrictions on plant movements or planting in other areas of New Zealand.
Mr Yard says the public has provided huge support to the response to date, with more than 1,000 reports of suspicious symptoms coming through MPI's Exotic Pest and Disease Hotline.
"We encourage people to keep looking out for signs of myrtle rust and telling us about it. Knowing where the disease is and treating it gives us the best chance of protecting some of our treasured plants into the future."