Polyphagous shot-hole borer: what the agencies record

This page reports what the official source says. It is not legal advice: ask the office named here. It covers polyphagous shot-hole borer, called PSHB, an ambrosia beetle that bores into trees and carries a fungus. The agency source is the Western Australia Department of Primary Industries and Regional Development, called DPIRD, which runs the response around Perth. All sources were read on October 8, 2026. The parent page, insect pests of trees, compares it with the other pests on the list.

Names

DPIRD uses polyphagous shot-hole borer and the scientific name Euwallacea fornicatus, abbreviated PSHB. The EPPO Global Database lists the code XYLBFO for Euwallacea fornicatus sensu lato, and a note dated December 2019 says it is considered a species complex that includes E. fornicatus sensu stricto, E. fornicatior, E. perbrevis and E. kuroshio.

What the agency says to look for

The DPIRD polyphagous shot-hole borer page (updated November 12, 2025) describes the beetle as about 2 mm long, the size of a sesame seed. It lists signs found when pruning: tiny 1 mm shot-holes, galleries or tunnels in the wood, branch dieback, staining or lesions, frass that looks like sawdust, gumming of resin and sap, and "sugar volcanoes", a white crystalline or foamy substance. It says detection can be difficult because the beetles are so small. The page says the beetle tunnels in trunks and branches and introduces a Fusarium fungus that it uses as food, and that the fungus spreads in the tree and disrupts the flow of water and nutrients, which may lead to tree death.

Hosts

DPIRD says over 500 plants and trees have been documented globally as affected, and publishes a list of affected plants and trees in Western Australia. The quarantine notice defines a host plant as one on that Western Australian host list.

Life cycle

The pages read give no life-cycle timeline. DPIRD says the beetle does not move far on its own but can spread easily through the movement of unseasoned wood, green waste and plant material.

Where it is reported

DPIRD says the beetle is native to Southeast Asia and has spread to countries including Israel, the USA, South Africa, Argentina and Western Australia. It says it was detected in Western Australia in August 2021, and that the detection area is the Perth metropolitan area. The national response is moving from eradication to long-term management, after the National Management Group determined eradication was no longer technically feasible. The page says that, apart from the department's tree pruning and removal program in the outer metropolitan area, landowners and managers in the Perth metropolitan area are responsible for managing borer-affected trees. No page for other states, New Zealand, the United Kingdom, Canada or the United States was read for this profile.

Regulated status

DPIRD says the beetle is a declared pest in Western Australia and a prohibited organism under section 12 of the Biosecurity and Agriculture Management Act 2007, and that any person who finds or suspects its presence must report it to the department. The quarantine area notice declares the whole of the Perth metropolitan region a quarantine area until 11.59pm on December 31, 2026, and names the local government areas, from the City of Armadale to the Town of Victoria Park. It divides the area into a Management Zone and a Containment Zone. It says failure to comply could result in a fine, remedial action by the Director General, or both.

What the agency says about moving wood and tools

The notice lists as controlled things: host plants with a stem greater than 2 cm in diameter, the beetle and its associated fungi, wood greater than 2.5 cm in diameter (other than wood treated or seasoned for 6 months or more, and construction, fencing, furniture, packaging and pallet products), and wood machinery used in arboriculture, mulching, chipping or handling wood. It sets out how each may move: wood chipped to pieces under 2.5 cm, or taken in a sealed and covered load to a listed waste facility; host plants inspected by a person certified through an approved course and moved within 7 days; machinery with all wood and plant material removed first. DPIRD's page repeats the 2 cm and 2.5 cm limits for each zone and says that tools, including chainsaws and woodchippers, that touch infested wood should be sanitised before use on uninfested trees, with 70% ethanol as the preferred disinfectant. It also says not to burn wood showing signs of borer damage, because the beetles disperse when infested wood is burnt. Related rules from other places are in the guides on moving wood and firewood and the biosecurity table by pest.

Who takes a report

DPIRD asks for signs of the borer or any other pest to be reported as soon as possible through its pest reporting app, or by contacting its Pest and Disease Information Service, and asks for a ballpoint pen or ruler in photos of bore holes to help assess size. Contacts for each country are on reporting a tree pest in Australia.

Management as the agency lists it

DPIRD's page lists, in general terms, using wood mulch from a reputable supplier or non-wood mulch, choosing native species over exotic ones, and training for landowners under an integrated pest management program being developed. This page gives no product names, rates or timings. For who may apply pesticides, see pesticide licences.