In this Inside Halton article, Matt Mayr from Davey's Northwest Toronto office shares advice on how to protect and treat your trees from the emerald ash borer. 

Posted: June 18, 2025

A large European mountain ash with thick foliage in front of a wire fence

If you have ash trees on your property you hope to save, protecting them against emerald ash borer is a must, according to Davey Tree Expert Company of Canada.

Matt Mayr, district manager of the Davey Tree office in northwest Toronto, said systemic insecticide treatment is the best option to save ash trees when applied in the spring or summer.

If you have untreated ash trees, they may already be stressed or dying from emerald ash borer.

In its larval stage, the emerald ash borer eats the tree’s cambium layer between the bark and the hardwood, leading to dead leaves and eventual tree death

Signs of Infestation: 

“When you start to see canopy dieback on your ash, that’s one thing to look for,” Mayr said. “When you start to see woodpecker holes, that’s another major telltale sign. The woodpecker is going after the beetle and the larva.”

To continue reading Matt's advice, click here

For more information, contact the Northwest Toronto office.

The Davey Tree Expert Company provides research-driven tree services, grounds maintenance and environmental and utility infrastructure consulting for residential, utility, commercial and environmental partners in the U.S. and Canada. Established in 1880 and headquartered in Kent, Ohio, Davey has over 12,000 employees who create and deliver sustainable solutions. Davey continues to grow through expertise with the SEED Campus, its newest commitment to training, research and safety. Become part of the Davey legacy by applying today and join one of the top ten largest employee-owned companies in the U.S.

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