Emerald Ash Borer

Q: What IS the Emerald Ash Borer (EAB)?

A: EAB is a highly destructive invasive pest that arrived in North America from Asia, most likely in untreated ash wood used for packing material. It was first detected in 2002 in Windsor, Ontario and Detroit, Michigan. Adults are metallic green in color, and about 1/2 inch long.

Q: How big is the problem?

A: The Canadian Food Inspection Agency (CFIA) data shows that Emerald Ash Borer (EAB) kills an estimated 97% of ash trees as the killing front moves through an area. Other agencies have found mortality rates as high as 99.9%.

IMPORTANT NOTE: EAB spreads via contaminated firewood and timber taken from infested areas, hitching a ride to new locations on unsuspecting vehicles.

Don't move firewood.

Help stop the spread of EAB - and avoid fines!

Q: Why does it matter?

A: It is important to retain some ash in the forest as EAB moves through, to provide for diversity, wildlife habitat, and a future seed source. Given the high mortality rate and the loss in wood value when trees die, a prudent landowner should consider careful management, to (1) optimize the value of their ash resource and (2) encourage the forest to become more resilient to EAB and other pests.

Q: What can we do?

A: Forest managers should begin considering their alternatives well in advance of actual infestation, especially in stands with over 30% ash. A stand management strategy should include plans for one or more action steps that take into account the owner’s objectives, the likely time frame of infestation, ecological and economic effects of ash harvesting/mortality (current and future stand dynamics), and strategies to minimize its spread.

For information on protecting important yard and amenity trees, see our TREATMENT page.

Q: Where can I go for more information?

A: To start with, you can click here to read “Managing Ash in Farm Woodlots: Prescriptions for Four Woodlots” (pdf), a technical paper authored by Peter Williams, M.Sc., R.P.F.

You can also check out the CFIA web page on the Emerald Ash Borer.