COMMUNITIES from Geraldton to Esperance have been asked to check their trees and shrubs for any signs of an exotic beetle to make sure it has not made its way into the regions.
The Western Australia Department of Primary Industries and Regional Development (DPIRD) confirmed the detection of the polyphagous shot-hole borer in a backyard maple tree in East Fremantle in 2021.
In an effort to determine how far the pest may have spread, DPIRD has implemented a surveillance program in the Mid West, Wheatbelt, South West and Great Southern.
Chief plant biosecurity officer Sonya Broughton said although the borer and its larvae would be hard to spot, as it spent most of its life inside a tree, there were symptoms to look out for.
"These include multiple entrance holes on the trunk or branches that are about the size of a ballpoint pen tip, crystalline foam (sugar volcanoes) exuding from the entry holes and tree wilting or dieback," Dr Broughton said.
"The top five trees to check are maple, willow, plane, coral tree and avocado as these are considered reproductive hosts in which both the beetle and the fungus establish and reproduce."
The tiny PSHB is exotic to Australia and considered both an agricultural and environmental pest, due to its wide range of host species.
"If established, the borer would have a significant impact on amenity trees and the fruit, nut, nursery and garden industries," Dr Broughton said.
"The borer can spread by flying up to 400 metres to neighbouring trees or by the movement of infested firewood, plants and green waste material, which is why we are expanding our surveillance program to regional communities.
"If residents do find something usual, we ask them not to remove it from their properties, and instead take photos and report to DPIRD."
A quarantine area notice is in place for 17 local government areas in the metropolitan area, including Cambridge, Canning, Claremont, Cockburn, Cottesloe, East Fremantle, Fremantle, Melville, Mosman Park, Nedlands, Peppermint Grove, Perth, South Perth, Stirling, Subiaco, Victoria Park and Vincent.
This means residents within the quarantine area cannot move any wood or plant material outside of this area that could host the borer.
Dr Broughton said a key message for regional residents who were having visitors from inside the metropolitan quarantine area are to remind their guests they cannot bring any wood or plant material that could host the borer from their homes to yours when visiting.
This includes live plants with stems greater than two centimetres diameter as they can host the borer.
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