How the Emerald Ash Borer became such a Problem in Ontario

Emerald ash borer (EAB) is a nasty little metallic blue-green bug, native to Asia, that attacks both healthy and stressed ash trees and has killed millions of these trees in southwestern Ontario and the Great Lakes States and poses a major economic threat to urban and forested areas in North America. The larvae of the EAB tunnels through the vascular system of the ash tree and cuts off the trees supply of water, nutrients, and sugar.

​This pesky invader was first discovered in Windsor, Ontario, and Detroit in 2002. It is believed to have been bought to the North American continent from eastern Asia in wood-packaging material in the early ’90s but went undetected until the population increased to dangerous levels. Scientists have concluded that there is no way to eradicate the emerald ash borer and the only hope for ash trees in Canada is to limit the spread of this pest.​​

The spread of the emerald ash borer​

But how has the emerald ash borer become such a problem, not only in Ontario but throughout Canada? We are the reason that emerald ash borer has spread so rapidly throughout Canada in the last few years. On its own, EAB can only travel a few kilometres per year, but it can easily conceal itself in the bark of trees, in logs, wood chips, timber or wood products and be rapidly dispersed across the country by people moving the infested material. The irresponsible behaviour of people is the main cause of the spread of EAB and the best way to limit the reach of this highly invasive bug is to act responsibly and avoid moving potentially infested ash material to non-infested areas.​

What the government is doing?​

The Canadian authorities have adopted a “slow-the-spread” approach to controlling EAB and to this end, the federal government has added restrictions to the shipment of ash trees and ash tree products in Ontario. Due to the major economic and environmental threat of emerald ash borer, the Canadian Food Inspection Agency has prohibited the movement of firewood and any material made from ash trees outside of designated areas under an Infested Places Order. Restricting the movement of ash tree articles and firewood will hopefully slow down the spread of the beetles. The government policy also includes a country-wide campaign of surveillance, regulation, enforcement, and communication and further regulatory measures are being considered.

​What can you do?​

While the emerald ash borer does not pose a risk to human health, it is lethal to ash trees and this has a negative impact on the environment, contributing to the loss of habitat and food for other species, which in the long run is extremely harmful to urban and rural diversity and could have a negative impact on our health. Unfortunately, the emerald ash borer has no known natural predators in Canada and there is nothing to control its population or spread. Once infected, the mortality rate of an ash tree is nearly 100%.

Every person needs to do their bit to halt the spread of the EAB. Be responsible for the transportation of timber and wood products and don’t take potentially infested material from the regulated zone to new areas as you may be aiding the spread of EAB.

You should learn to identify the signs of an infestation, which include dead branches, yellowing leaves and the thinning of the crown of the tree. You also need to be able to identify the emerald ash borer. The adults are metallic blue-green in colour with narrow bodies and the larvae are creamy white with light brown heads.

If you see emerald ash borer or signs of infestation, call the Ontario Ministry of Natural Resources at 1-800-667-1940 or the Canadian Food Inspection Agency at 1-800-442-2342. You can also report sightings to the toll-free Invading Species Hotline at 1-800-563-7711.
Martin’s Tree Service can help you identify trees that have been infected by EAB and advise you on the best course of action.