Frequently Asked Questions
WHAT IS EHB?
About EHB
EHB is an exotic pest of seasoned softwood timber including pine, spruce and fir. EHB larvae can cause serious damage to the wood it infests, which includes untreated structural pine timber, to the point where floors and roofs can collapse.
In Western Australia, EHB has only been detected in seasoned (dry) untreated pine in Western Australia.
Description refer to Exotic Pest Fact Sheet
Adult EHB beetles are brownish-black and may have white patches on their back. Behind the head there are two raised, black, shiny knobs. Adults are about 1-2cm long with antennae about half that length.
Larvae (grubs) in tunnels or galleries in the wood are a creamy white colour with a rippled body and enlarged head. Larvae can grow up to 4cm in length.
What threat does EHB pose to Western Australia refer to EHB Newsletter Edition Five
If EHB were to become established in Western Australia, those buildings and houses built with untreated structural pine timbers, such as those in the more newer suburbs of Perth, would stand a high risk of infestation, which could result in structural damage and injury to inhabitants.
There would also be an increased threat of EHB becoming established in other States, which would cost the softwood timber industry and the Australian economy billions of dollars in treatment and repair costs.
EHB larvae bore through wood without ever breaking the surface, and can live inside untreated pine timbers and deadwood inclusions in live pine trees between two and 10 years before emerging through exit holes as an adult beetle. This makes them almost impossible to detect.
What are the signs of EHB? refer to EHB Newsletter Edition One
- Characteristic oval shaped exit holes (5 -10 MM in length)
- Frass, which is a mixture of fine powdery particles of wood, dust and excrement
- Soft scraping sounds which may be heard as EHB eats through the timber
- Galleries, tunnels and larvae may be evident in untreated pine timber that has been planed, sawn or split.
Where has EHB been found?
EHB has been detected on 144 properties across 30 Perth suburbs, primarily in the Mundaring Hills and Gnangara/Ellenbrook areas. 113 out of these properties have been cleared of all EHB host material, including live pine trees, which sometimes have dead areas where EHB can lay eggs. View updated information on where EHB has been confirmed.
HISTORY
Where did EHB come from?
EHB was first discovered in Europe - hence the name European House Borer. However, the pest has since been found in the Middle East (Turkey), North Africa, South Africa, South America, USA, China and Asia Minor. EHB probably made its way into WA in a piece of imported timber as a larva and continued to spread from there.
In South Africa, where EHB was first discovered in pine plantations before infesting structural pine in houses and buildings. About 90 per cent of house roofs in suburbs adjacent to these plantations became infested which resulted in large scale collapse.
Have there been any previous infestations in Australia?
EHB has been detected several times in Eastern Australia but those infestations were eradicated by fumigation. Eastern Australia did not have the problem of large scale infestation in pine trees, dead wood material and untreated pine timbers and furniture. Infestation was the result of imported houses from Europe.
How far can an adult beetle travel?
An adult EHB beetle may only travel a minimal distance if its food source has not yet been exhausted, which can take more than 10 years.
A major concern is that migration of original EHB populations from the hills region to Gnangara is considered likely, as DNA testing has indicated populations to be closely related, and there is speculation that further migration is possible.
This is due to prevailing easterly and south-easterly winds in Perth summers, which coincide with the EHB flight season, and the presence of pine tree host bridges (some infested) between the two areas.
WHAT IS BEING DONE?
Response Strategies
In accordance with an Emergency Plant Pest Response Plan (volume 2), approved by the Primary Industries Standing Committee in 2006, the threat of European House Borer will be tackled through:
Eradication - this will be achieved through the destruction of host materials within infested areas, including live trees and deadwood pine material.
Surveillance - will be undertaken through delimiting surveys (from Geraldton to Esperance, every road is travelled to inspect host material), buffer surveys (door knocking of properties within infested areas to determine untreated pine wood presence and possible infestation), roof inspections (inspecting a selection of houses and researching new detection methods), the trap pole program (to assess EHB presence where host material has been removed) and Dectector Dogs.
Movement controls - once an infested site has been identified, a Priority Management Zone (PMZ) is declared over all properties within a 100 metre radius of the point of infestation. All host material within a PMZ is destroyed and trap poles are placed for ongoing detection. Restricted Management Zones (RMZ) are also declared within a minimum 2km radius from an infested property. The movement of EHB host material in and out of RMZ and PMZ areas become subject to regulatory controls and restrictions.
Destruction and disposal of infested material - pine tree removal is undertaken by private contractors under the supervision of EHB staff. Trees and infested material are destroyed by chipping which renders the material unsuitable for EHB development and survival.
Removal of Infested Pine Trees Refer to Pine Tree Removal fact sheet
EHB can live in small, dead sections of live pine trees. Where exit holes are discovered in trees, it means an EHB adult beetle has emerged and that EHB larvae may still be inside. These trees must be removed and destroyed to prevent the survival of further EHB adults, and the possible migration to other host materials to lay eggs.
Why do healthy pines need to be removed? Refer to Pine Tree Removal fact sheet
Many pine trees are mature and therefore contain much dead wood, which can harbour EHB. As these deadwood inclusions can be difficult to detect, all trees surrounding the identified infestation have a high probability of being infested and must therefore be removed to prevent further spread.
Will pine tree removal destroy the aesthetic value of bushland suburbs?
EHB contractors have been well briefed to ensure that no native shrubs, trees or fauna are damaged or destroyed while removing pine trees.
Have any Perth homes been infested? Refer to EHB Newsletter Edition Five
Yes. EHB was recently discovered in a house in Brigadoon, which is a suburb close to the Gnangara/Ellenbrook area. The infestation is likely to be the result of a migration from nearby infested pine trees. The find has confirmed the urgency of removing pine trees and pine waste material from areas where infestations have been found. In the case of the house in Brigadoon, both larvae and exit holes were discovered in fine timber beams supporting a second story. A number of beams had been eaten away and could have resulted in a floor collapse if not discovered.
The Department of Agriculture and Food WA (DAFWA) suggests that the lack of infestations in roofs to date has been due to the fact that untreated pine has only been used since 2000, and that it is too soon to see infestations because of the EHB long life cycle.
Why can't the trees be monitored instead of removed? Refer to EHB Newsletter Edition Five
EHB has a long life cycle which results in a slow build-up of EHB populations and a low rate of natural spread. Accordingly, there has been some public argument that pine tree removal in infested areas can be delayed to allow for further research in surveillance options. This is not supported by the specialist Scientific Advisory Panel (SAP) overseeing the EHB program for national and State Government partners.
Any delay of host material removal will only lead to further spread and increase the risk of eradication failure. Without eradication, other States in Australia would also become at risk. This could be devastating for Australia. In South Africa, where EHB was first discovered in pine plantations before infesting structural untreated pine in houses and buildings, about 90 per cent of house roofs in suburbs adjacent to these plantations became infested which resulted in large scale collapse.
Why can't EHB be managed like in other countries? Refer to EHB Newsletter Edition five
Options to manage EHB include detector dogs and prototype acoustic equipment developed by Edith Cowan University. However, EHB is managed only when eradication is impossible. The acoustic devices will be used to monitor trap poles put in place to ensure eradication following the removal of pine trees.
A Benefit Cost Analysis, conducted with assistance from the Australian Bureau of Agriculture and Resource Economics, shows that from an economic perspective, eradication is the most cost effective option. In fact, a cost benefit analyses shows a cost:benefit ratio of 64:1. That is, every $1 spent on eradication will eliminate $64 worth of damage and timber treatment across Australia.
A nil control approach would create economic damage across Australia to an amount of $2.4 billion over a 30 year period and more than $6 billion over 100 years. Even limited containment would cost Western Australia approximately $345 million over 30 years. In comparison, the cost of eradication from 2004 to 2021 (17 years) has been estimated at only $50 million, and this cost is currently funded through a national cost sharing agreement by all States and Territories, and the Federal Government.
Why can't EHB be managed like other pests, such as termites?
It is possible to protect houses against termites but not EHB. Termites can only enter houses through burrowing. Therefore, chemical treatments and other barriers can be placed beneath houses to prevent infestation. In the case of EHB, beetles can fly in through any open space and lay eggs in the first wood crack found.
Is Eradication Feasible?
Eradication in Western Australia is considered possible due to a number of factors:
- EHB is primarily confined to the greater metropolitan areas
- EHB have a slow natural spread due to a long life cycle and tendency to lay eggs in the same piece of wood they emerged from
- EHB has been found only in pine trees, materials and products
- There has been successful eradication in other States
Is there a guarantee that EHB will not infest Western Australia again?
We can not guarantee that that EHB will always be detected by Western Australian quarantine procedures, although detector dogs and acoustic equipment will significantly reduce the risk.
Additionally, a major pine supplier plans to install new equipment towards the end of 2009 which will increase the availability of treated pine, and also lower the additional cost of using treated pine in housing construction.
The Department of Housing and Works is also proposing a change to the Australian Building Code to include a mandate that treated pine must be used where areas are subject to EHB Priority Management Zones.
With these changes in place, and with the extensive removal of pine trees from susceptible suburbs, EHB food sources will be significantly reduced, therefore making any future infestations easy and cost effective to manage and eradicate.
OPTIONS
What should I do if I think I have EHB on my property? Refer to European House Borer Newsletter Edition One
Please contact the free call EHB hotline on 1800 084 881 to report the suspected find, and further instructions will be provided.
I am about to build, what should I put in my roof?
EHB only attacks untreated, dry (seasoned) pine. Treated pine and other roofing materials are not at risk from EHB. The building advice from the Department of Housing and Works is not to use untreated pine for structural purposes in affected areas. You should seek advice from your builder about the most suitable option for your home, or contact the Department of Housing and Works Building Codes and Regulations Branch on (08) 9440 2349. Treatment options are also available on the Department of Consumer and Employment Protection website.
I have an untreated pine roof. What can I do?
First have your roof inspected regularly. If exit holes are found, please call the free call EHB Hotline on 1800 084 881 and we will send someone to identify whether it is EHB, at no cost to you.
I'm about to buy a house. What can I do?
You can contact an EHB accredited pest controller to perform an inspection, which is similar to a termite inspection. A list can be found at the Department of Consumer and Employment Protection website.
How can I find out if I have untreated pine in my roof?
You need to ask your builder. Alternatively, contact The Building Commission for further details.
How can pine or pine products (such as furniture) be transported out of PMZs and RMZs?
Please call the free call EHB Hotline on 1800 084 881 to speak with someone about your requirements. In the case of pine furniture, if it was purchased painted or varnished, or has been stored inside for its entire life, it is not subject to regulations restricting movement.
In summary, no untreated pine materials or products can be taken out of an RMZ without appropriate treatment, fumigation or authorisation from an EHB Response officer. Penalties apply should regulations be breached.
Will areas of large scale tree removal be replanted?
Discussions have already been undertaken with landscapers from local governments about appropriate species for replanting once the pine trees have been removed. Although this will remain a local government responsibility.
For more information about EHB and the EHB response, visit www.ehb.wa.gov.au or freecall 1800 084 881
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