Perth homes at risk of infestation by European house borer

ALMOST 300,000 homes are at risk of infestation by the little-known European house borer, according to the State Government. The Government has just announced it is committing $4.9 million over four years to a program designed to control the spread of the destructive timber pest with a taste for seasoned softwood, including pine. The funding will help protect new and existing homes from the borer, which is likely to have arrived in WA as larvae in imported timber.

Agriculture and Food Minister Ken Baston said EHB was a destructive insect that attacked seasoned softwood, including pine.

“Without appropriate action, EHB has the potential to infest and damage the structural integrity of homes and buildings built with untreated pine,” Mr Baston said. “This investment will help protect 300,000 Western Australian homes which could be at risk of infestation because they are built with untreated pine. “The program, run by the Department of Agriculture and Food WA, will provide surveillance to protect new and existing housing, enable localised eradication and restrict the movement of host timber material within management zones to limit the further spread of EHB.”

Since first detected in 2004, an eradication and containment program has confined EHB to isolated pockets within the greater Perth metropolitan area, including Ellenbrook. The spread of EHB is slow and it takes four to seven years to spread over several hundred metres of infested sites.

“Without a containment program, all of Western Australia would be considered infested with EHB and all exports of EHB carriage material — including structural timber, furniture, pallets, crates, boxes and dunnage — would be subject to export restrictions,” the minister said.

According to the experts, untreated pine is the main concern in WA. They say the EHB insect pest goes for untreated, seasoned and dry coniferous timbers, including pine, fir and spruce. Larch, hoop and bunya pine are also believed to be susceptible to damage by the borer. Fortunately, actual home cases are rare.

Novel audio listening devices, which detect the unique “crunching” sound made by the borer, are still in a trial phase. With the new surveillance plan, pine trees in the metropolitan area will be inspected to enable eradication of the borer before they spread. EHB only attacks soft wood and is currently contained largely within plantations and is not established in most areas. But unlike termites, the borer cannot be stopped with a chemical soil treatment or barrier treatment, because it is a flying pest and all potential host material would need to be treated.

Chemical treatment hasn’t proven effective and is complicated, prohibitively expensive and, because of the nature of the chemical, is impossible to apply in inaccessible places. In the home, these include joints and bearers covered by gyprock, WA experts say. Also unlike termites, visible signs of borer infestations are hard to detect until serious structural damage occurs.