Polyphagous shot-hole borer
Polyphagous shot-hole borer is an invasive beetle species that infests a wide range of trees, causing damage by boring into the wood and spreading pathogenic fungi. A Quarantine Area divided into two zones is in place with rules applied to the movement of wood or plant materials.
About the Polyphagous shot-hole borer
Polyphagous shot-hole borer (PSHB, Euwallacea fornicatus) is a small beetle native to Southeast Asia that tunnels into the trunks, stems and branches of trees and plants. This beetle is highly invasive and attacks a wide range of plant species, with over 500 documented globally to have been affected.
The department is responding to a detection of this invasive pest in the Perth metropolitan area and has implemented a Quarantine Area (QA). This restriction aims to prevent the spread of the pest by limiting the movement of wood and plant materials.
PSHB was detected in WA in August 2021. Since then, the department has been leading a nationally funded and coordinated biosecurity response. Allowing this pest to spread in WA could have a significant impact on our urban canopy and may pose a threat to our valuable agricultural industry.
Current situation
The National Management Group - responsible for directing eradication programs for exotic pests and diseases – met on 18 June 2025 and determined it was no longer technically feasible to eradicate Polyphagous shot hole borer from Western Australia.
A national Transition to Management (T2M) plan is now being developed to transition from the eradication response to a management phase from 1 July 2025.
The National Management Group’s determination considered the latest scientific data and advice from plant biosecurity experts - highlighting the difficulty in early detection, control before reproduction and the lack of proven effective chemical treatments.
The department will lead the transition to management in WA to minimise the impact of shot-hole borer on Perth’s tree canopy and help protect the State’s horticultural industries.
Over the next 18 months, the department will work with industry, community and local government partners to build capacity to manage the pest.
Work will be undertaken to build upon the WA Agriculture Research Collaboration research projects to explore improved surveillance and treatment options to support the long-term management of the pest.
Suspect an infestation?
Report a suspected PSHB infestation by using the MyPestGuide® Reporter app.
Report via MyPestGuide
Quarantine Area
The PSHB Quarantine Area (QA) will remain in place as a key measure to limit the spread of the pest. The QA covers the entire Perth metropolitan region, encompassing 30 local government areas across more than 6400km2.
Movement Restrictions
To slow the spread, movement of PSHB material is restricted under the following rules:
- Movement of PSHB host material within the QA is discouraged.
- Movement of PSHB host material from within the QA to areas outside is prohibited.
These restrictions apply to material such as tree prunings, mulch (>2.5cm diameter), unseasoned wood, and plants (>2.0cm diameter).
Enter an address into the interactive map below to see which restrictions apply to your property.
What plants are affected?
PSHB causes serious damage to many types of trees and plants with a global host list covering over 500 species. When infested, a plant can show symptoms such as dieback, shotholes, galleries, frass and gumming.
Reproductive hosts are susceptible trees in which both the beetle and the fungus successfully establish and reproduce. The global host list is extensive with over 100 reproductive hosts.
View the list of affected plants and trees in Western AustraliaKeep an eye out
Detection of PSHB can be difficult as they are very small – roughly the size of a sesame seed. However, there are several symptoms that can indicate a plant may be infested.
Watch the animation below on YouTube to learn more and find out how to report PSHB sightings.
How does PSHB spread?
PSHB is a tree-boring beetle that has a symbiotic relationship with a Fusarium fungus. It cultivates this fungus inside of plants as a food source for themselves and their larvae. In susceptible species, the fungus kills the plant by restricting or preventing the movement of water and nutrients. This causes symptoms such as Fusarium dieback that eventually leads to plant death. The beetle also causes structural damage by creating tunnels, known as galleries, throughout the plant.
Native to Southeast Asia, PSHB has spread to countries including Israel, the USA South Africa and Argentina, and is now in WA. It is possible PSHB ‘hitchhiked’ its way to Australia on untreated wooden articles and packaging materials. Subsequent spread can be aided by the movement of infested wood (such as pruned trees, firewood) or wooden products such as furniture.
Actions to minimise the spread
- Monitor susceptible species including your local street and park trees for signs of PSHB damage and report any suspicious infestation signs to the department.
- Talk to your family, friends and neighbours to spread awareness to this invasive beetle
PSHB does not move far on its own but can travel long distances when people unknowingly intervene. Firewood can catalyse and provide a great mechanism for the distribution of PSHB without you knowing.
- Don't move firewood long distances including when you go camping - buy it where you burn it.
- Don't burn wood from host trees, especially if it looks like it has borer damage. PSHB beetles disperse when infested wood is burnt.
- Use grass clippings or compost as mulch as possible in your garden as wood chips from non-reputable places can spread PSHB
- While pruning or gardening check your plants and branches for sign of PSHB
- Disinfect pruning tools. Any tools (including chainsaws and woodchippers) that come into contact with infected wood should be sanitised before using on uninfected trees
- Avoid moving plants or wood products too far from your local area inside the QA
- Don’t move plants, wood or green waste from a known PSHB infestation area
- Follow the current QA requirements
- Plant native species over exotic plants
- Don’t take it upon yourself to dispose of a possibly infested plant
- Contact the department regarding any questions or advice
Legal duty to report
Euwallacea fornicatus (Eichhoff, 1868) is a declared pest in WA. It is a prohibited organism under section 12 of the Biosecurity and Agriculture Management Act 2007.
This means that any person who finds or suspects the presence of polyphagous shot-hole borer must report it to the department.
More information
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PSHB Alert factsheetpdf (537 KB)
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PSHB Frequently Asked Questionspdf (386 KB)
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PSHB Transition to Management Frequently Asked Questionspdf (208 KB)
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PSHB Quarantine boundary mappdf (423 KB)
Polyphagous shot-hole borer Quarantine Area - September 2024
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PSHB Quarantine Area Noticepdf (201 KB)
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PSHB Affected plants list - WApdf (389 KB)
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PSHB Affected plants list WA - Susceptibility methodologypdf (261 KB)
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PSHB Affected plants list - Globalpdf (636 KB)
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PSHB Approved green waste sitespdf (144 KB)