Painted Apple Moth – Progress Reports
Site 1: Glendene
The latest check for painted apple moth within the one kilometre radius survey zone in the west Auckland suburb of Glendene indicates that control measures are proving effective.
The insect was first reported in Glendene in early May of this year.
Of the 1350 sites within the zone, the insect had previously been found on 22 properties. The latest survey found caterpillars are now confined to only three of these properties.
The insect has been controlled using a widely-used organo-phosphate insecticide known as chlorpyrifos (pron: clor-pirro-fos) which was applied from the ground to host trees on the infested properties, as well as surfaces of buildings and other equipment or containers.
This insecticide was registered in the early 1970s and has been widely used by farmers and horticulturalists for the last 20 years. It is commonly used to treat apples, pipfruit, stonefruit, kiwifruit and other crops as well as ornamentals for caterpillars and other insect pests. It is also a component in certain animal remedies, such as pour-ons used treat sheep for lice and ticks, and as a flea control in cats and dogs.
Selected host trees were also removed from infested properties as part of the control programme.
Site 2: Mt Wellington/Panmure
Progress in surveying the one kilometre radius zone in the Mt Wellington/Panmure area for the painted apple moth has been hampered due to bad weather.
However, with more than three-quarters of the zone checked, it appears that the insect is confined to 11 properties.
Host trees on the infested properties have been ground sprayed with chlorpyrifos (see above). For future spraying, consideration is being given to using an alternative chemical, deltamethrin (trade name Decis Forte), which can be used at extremely low dose rates. Host trees have also been removed where appropriate.
The Ministry of Agriculture and Forestry’s Director of Forest Biosecurity, Dr Ruth Frampton, said there was no evidence to suggest that the Glendene and Mt Wellington/Panmure infestations were in any way linked.
The Mt Wellington/Panmure infestation is some 15 kilometres away from Glendene. Because the female moth does not fly, the natural spread of this pest is limited to about 200-300 metre “hops”. “It therefore seems highly unlikely that since May the painted apple moth had spread from Glendene to Mt Wellington,” Dr Frampton said. “What seems more likely is that we are dealing with two separate infestations.”