The Emerald Ash Borer (EAB) which has devastated ash trees in southwestern Ontario and parts of the United States since its discovery in Detroit, Michigan in 2002, has been detected in the City of Toronto. The EAB is an introduced insect pest from Asia that attacks and kills all species of ash (genus: Fraxinus) trees.
What is the Emerald Ash Borer (EAB)?
EAB is an introduced insect pest from Asia that attacks and kills all species of true ash trees (genus: Fraxinus) by feeding beneath the bark and disrupting the flow of water and nutrients within the tree.
How much damage can the EAB cause to trees?
Tree mortality will result if a tree has been infested with EAB. Mortality may occur in as short a period as one year, however, death normally occurs within 2-3 years of a tree becoming infested.
How can I tell if I have an ash tree on or near my property?
Link: How to identify Ash Trees (PDF)
Link: City of London ash tree identification document (PDF)
How can I tell if an ash tree is infested by EAB?
Unfortunately, this is extremely difficult. Without cutting the tree down and skinning off most of the bark, it can be difficult to determine whether a tree is infested. A lot of the symptoms associated with EAB, such as shoots (suckers), cracking bark, D-shaped holes and thinning crowns only become evident after two or more years of infestation. One or more of these symptoms may appear even without the presence of EAB.
Link: Canadian Forest Service “A Visual Guide to Detecting Emerald Ash Borer Damage” (PDF).
What will happen to the City-owned ash tree on or near my property?
Urban Forestry plans to remove dead and dying City-owned ash trees and will replace them, where space permits, as soon as possible. Homeowners will be notified of tree removal and replacement planting.
What should I do if I have a privately-owned ash tree on my property?
Property owners are responsible for taking care of privately-owned trees. The City recommends you monitor the condition of your tree, looking for signs of infestation. Most ash trees in Toronto are expected to deteriorate considerably and die over the next several years. When you see signs that your ash tree is dead or dying, you should contact a professional tree care company (you can find these in the Yellow Pages and other business directories). You should choose an arborist certified with the International Society of Arboriculture (ISA) or registered with the American Society of Consulting Arborists (ASCA). Make sure to ask if there is a fee for inspection and quotes; some companies provide these services free of charge.
If your ash tree appears healthy, you may consider asking your arborist to assess whether the tree may benefit from TreeAzin injections (link to TreeAzin portion of `Managing the Impact of EAB.) In some cases, TreeAzin may be able to slow the EAB infestation within a single tree.
Private property owners are strongly encouraged to consider planting new trees before or after ash tree removal. Healthy trees can increase property value, help cool your home and clean the air, along with other environmental, economic and aesthetic benefits.
Do I need a Tree Removal Permit?
For trees on Private Property.Click here.
For trees within a Ravine Protected area. Click here.
For more information visit: www.toronto.ca/eab











