The Department of Primary Industries and Regional Development (DPIRD) is urging metropolitan gardeners to maintain vigilance during winter and continue to look for and report two significant exotic plant pests.
Acting Chief Plant Biosecurity Officer at the Department, Vincent Lanoiselet said Queensland fruit fly (Qfly) and polyphagous shot hole borer (PSHB) remained active despite cooler temperatures.
“While Qfly and PSHB activity does slow somewhat during the cooler months, the mild Perth temperatures are still warm enough for these serious exotic pests to proliferate,” Dr Lanoiselet said.
“Winter fruits like citrus are susceptible to Qfly as the pest takes refuge on the underside of evergreen trees, where it can be two-to-three degrees warmer than air temperature.”
He said PSHB activity was not likely to slow with a moderate winter forecast. The wood borers could even benefit from winter storms as infested trees could lose limbs and provide havens for them.
Quarantine Areas remain in place for both Qfly and PSHB, requiring affected residents and businesses to adhere to movement restrictions to stem the spread of these pests.
Dr Lanoiselet said the Qfly Quarantine Area included movement conditions within a 1.5-kilometre radius of the Bayswater detection.
“Residents and businesses in this Corrective Action Zone cannot move home-grown fruit and fruiting vegetables, like tomatoes, chillies and capsicums, out of or within the area, unless cooked, frozen or solarised,” he said.
“Unwanted fruits and fruiting vegetables can be treated by cooking, freezing or solarising before being disposed of in general waste bins.”
He said more than 70 DPIRD officers continued to survey the area, while the permanent early warning Qfly surveillance grid had been supplemented with additional traps near the detection point and high risk areas.
Dr Lanoiselet said the Quarantine Area for PSHB was also in place for 25 Local Government areas across most of the metropolitan area, where Department officers continued to survey for signs of the tiny borer.
DPIRD is to share information about Qfly and PSHB, as well as other pests and weeds, at the Perth Garden & Outdoor Living Festival until 14 May in the Nursery & Garden Industry WA marquee.