Emerald Ash Borers are a non-native species that feed upon the bark of ash trees. They were discovered in Canada in 2002 and they are extremely destructive to all ash trees. Emerald Ash Borers are responsible for killing millions of ash trees in Ontario as well as the United States. Billions of trees are at risk with this invasive species and they pose a major economic and environmental threat to all regions impacted. This species was responsible for several initiatives including restrictions on firewood transportation in and out of Ottawa and Gatineau or adjacent communities.


Emerald Ash Borers are between 8.5 and 14 milimetres long and appear like a metallic blue-green beatle with a narrow body. These insects typically have a one to two year life cycle and they lays eggs on tree bark and in bark crevices starting in May. If any trees on your property are currently being invaded by Emerald Ash Borers, you can keep an eye out for a few of these signs and symptoms:

  • The ash trees on your property appear to be thinning at the top
  • Your ash tree branches have rapidly died off within the span of less than a year
  • Your ash tree branches are dying and leaves are yellowing
  • O or D-shaped exit holes and vertical cracks in your ash tree trunk
  • S-shaped grooves in tree bark
  • Frequent woodpecker sightings or woodpecker holes in your trees


There are three types of ash trees in Eastern Ontario: white, green/red, and black ash. Ash trees are commonly found in public areas along streets, within parks, and within forests throughout Ottawa and Ontario. If you’re unsure of what types of trees are on your property, or you’re noticing these signs in a more public area, here are a few telltale signs that you may be looking at an ash tree:

  • They are usually around 30 metres tall
  • All leaves and buds are symmetrical with them growing on opposite sides of a branch
  • Certain trees may show seeds that grow in clumps with individual seeds being the shape of oars
  • They often have a diamond-shaped bark pattern on their trunks

Several common trees within Ottawa can be easily confused with ash trees. If you’re unsure whether or not the trees on your property are at risk, contact the certified arborists at Croft Tree Experts. We will be happy to investigate your property and provide you with definitive answers and how to best proceed.

Two woodpeckers on a ash tree infested by emerald ash borers


Invasive species like Emerald Ash Borers should be reported and handled immediately. There is still currently an Ottawa tree insecticides injection program to treat certain areas with ash trees. Addressing Emerald Ash Borers is very much an ongoing project in order to keep the species under control. There are currently replanting initiatives in place as well.

Here at Croft Tree Experts, we will gladly inspect the trees on your property, and help provide recommendations on the next steps. Whether the best course of action is to perform tree removal services and replant a new one or treat your tree if the damage isn’t too severe.

In addition to insecticide injections, there are a few other effective methods to treat areas that have been infected by Emerald Ash Borers. Some of the more common treatment methods include the soil drench method and the surface spray method. The soil drench method involves getting a certified arborist to drench all of the soil surrounding the tree and its roots with insecticide. The surface spray method is another effective way to eliminate invasive species. This method involves spraying the ash tree directly with insecticides


We’ve created this page for Ottawa homeowners, commercial property owners and property managers as a resource for Emerald Ash Borers Ottawa. As Certified Ottawa Arborists, we have undertaken thousands of projects over the years. If you’re at all concerned about Emerald Ash Borers invading your area, contact the specialists at Croft Tree Experts. We will be able to visit your property and provide a free assessment and identify any invasive species or problems with the trees on your property. Whether they might be Emerald Ash Borers or another dangerous species, we’ve got you covered!

Our team has over 65 years of experience and we are the go-to certified arborists in the Ottawa area. We are WSIB insured, offer competitive rates, can obtain all the proper city permits for you, and provide 24/7 Standby emergency services. Contact us today!

Croft Tree Experts team of certified arborists.

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Contact Us

Reach out to Croft Tree Services today! We are more than happy to respond to any inquiries or questions you may have. We are committed to working with you to find the right solutions and the most convenient scheduling options for your Ottawa tree care services, tree removal and landscaping needs. Please be as specific as possible in the field below, so that we can help you in the most effective way.


    208 Royalton Private
    Ottawa, ON K1V 9S3

    (613) 883 5611 or  (613) 410 4677


    Monday to Friday: 8am to 6pm
    Saturday: 9am to 3pm
    Sunday: Closed