Emerald Ash Borer


The Canadian Food Inspection Agency has issued a ministerial order to prohibit movement of firewood, and ash-tree products such as nursery stock, logs, branches and wood chips from areas of Ottawa and Gatineau to any other surrounding regions to limit the spread of Emerald Ash Borer (EAB).

Emerald Ash Borer - Photo courtesy of David Cappaert, Michigan State University

Emerald Ash Borer is a non-native, highly destructive wood-boring beetle that feeds under the bark of ash trees. All species of ash are susceptible to attack, except mountain ash, which is not a true ash species. Since it was first identified in Michigan in 2002, EAB has killed millions of ash trees in Ontario and many parts of the United States. It poses a major economic and environmental threat to urban and forested areas. It was confirmed in Ottawa in 2008 and its impacts can be clearly seen spreading from the St. Laurent area. Since the insect spends most of its lifecycle under the bark of trees, it can be easily moved with firewood or other tree materials such as nursery stock, logs, brush and larger wood chips. This insect is able to fly, but since its spread has been primarily along major highways and transport routes, it is clear that humans are the main vector of dispersal.

Emerald ash borer forum presentation [ PDF – 2.2 MB ]

Ward Map [ PDF – 11 MB ]


What EAB does:

Emerald Ash Borers normally have a one-year life cycle, but some can take up to two years to mature. EAB lays eggs on tree bark and in bark crevices starting in late May.

In its larva form, which resembles a caterpillar, Emerald Ash Borer feeds just under the bark of ash trees. This feeding disrupts the tree’s circulation of water and nutrients. The presence of even a few insects in a tree can kill it.

Top branches of ash trees usually die off first. Trees can lose half its branches in a single year. Once larvae finish feeding under the bark, they mature into adult beetles that chew their way out of the tree.

S-shaped grooves and D-shaped exit holes 3.5 – 4 mm wide caused by adult beetles photo courtesy Troy Kimoto, CFIAS-shaped grooves and D-shaped exit holes 3.5 – 4 mm wide caused by adult beetles photo courtesy Troy Kimoto, CFIA
  • look for loss of leaves and dead branches in the upper part of ash trees
  • unusually thin tree crowns
  • branch and leaf growth in the lower part of the stem where growth was not present before
  • unusually high woodpecker activity
  • look for bark splitting, S-shaped grooves beneath the bark caused by larval feeding, and D-shaped
  • exit holes 3.5 – 4 mm wide caused by adult beetles

Infested ash trees in North America generally die after two to three years, but heavily infested trees have been observed to die after one year.


Ash Trees:

Learn how you can identify Ash trees.


The City of Ottawa’s Emerald Ash Borer Strategy:

The City’s Emerald Ash Borer (EAB) strategy includes treating trees with TreeAzinTM, removing and replanting trees, proactive plantings, as well as public education to raise awareness regarding EAB and proper wood handling and disposal.


Selective Tree Injections:

The City is treating selected ash trees throughout the Ottawa region with TreeAzinTM. TreeAzinTM is a systemic insecticide produced from extracts of Neem Tree seeds (Azadiracta indica).  It is injected under a tree’s bark, directly into the conductive tissues, and moves upwards with the flow of water and nutrients.  TreeAzinTM can be very effective at controlling EAB infestations but injections are required every two years and treatment does not ensure tree survival.  For more information on TreeAzinTM, please visit the manufacturer’s website at http://bioforest.ca/.

Because of the large population of ash trees in Ottawa, it would be prohibitively expensive to inject every ash tree on city property. The City’s injection program, therefore, focuses on injecting ash trees that will receive the most benefit. The City’s injection policy aims to:

  • Protect a mix of age classes to ensure diversity in the population of protected ash trees, and
  • Provide ash tree protection in neighbourhoods with a high percentage of forest cover from ash species

Trees are assessed on an individual basis and considered for injection based on a number of factors including tree health, tree form and tree location.

If you would like a City-owned tree considered for our 2013 injection program, please call 311.


Are you thinking of having your privately-owned ash tree injected?:

Treating your ash tree can be a good investment when taking into account the cost for tree removal and replanting as well as the benefits urban trees provide including increased property value and energy savings.

To input information about your existing ash tree, your potential replacement tree, and other economic factors that impact the analysis of whether to treat or remove your tree, please visit: Canadian Forest Service – Ash Protection Model (CFS-APM)


Slow down the spread:

Residents can help by:

  • Learning to identify EAB and ash trees
  • Reporting suspected outbreaks
  • Not moving firewood out of Ottawa and Gatineau or into adjacent communities
  • Being aware of regulations for firewood and ash products
  • Not bring firewood to your cottage or campsites
  • Buying your firewood locally and know where your firewood originates
  • Obeying all ministerial orders issued by the federal government
  • Remembering, even after an infested tree has been cut down, EAB continues to live in the wood

Failure to obey a ministerial order can further put our forests at risk, and could also lead to prosecution and fines as high as $50,000.


Removal and disposal:

The City is responsible for maintaining or removing City-owned ash trees (in City road allowances, municipal parks and natural areas, and on the City-portion of private lots). Trees will only be removed if they are highly infested with the Emerald Ash Borer (EAB) or if they become structurally unstable.

Private property owners are responsible for removing and disposing of affected ash trees on their properties. It is recommended that the owner use a certified arborist and ensure full compliance with the ministerial order for wood movement and disposal.

Home owners are still able to put leaves and branches under four inches in diameter and four feet in length out for curbside leaf and yard waste collection even if they are from ash trees. Residents can continue to bring their own leaf and yard waste to the Trail Waste Facility for free if it meets the above requirements. A fee of $90/tonne will apply to contractors and residents bringing in material greater than four inches in diameter


Don’t move firewood:

The human movement of infested materials such as firewood, logs, branches, nursery stock, chips or other ash wood is the most common way EAB has been spread. Adult Emerald Ash Borer can fly, but research indicates adults usually fly a short distance upon emergence. The City of Ottawa and the CFIA are asking the public not to move firewood or other wood materials. To reduce the risk of spreading forest pests, buy and burn firewood locally.

You can help by learning to identify EAB and ash trees and by reporting suspected outbreaks of the Emerald Ash Borer by contacting the CFIA at 1-866-463-6017 or e-mailing the City 311@ottawa.ca. For more information see the Ontario Ministry of Natural Resources’ EAB Site.