I keep thinking back a year ago to a hot, summer day when I was completing a tree health assessment for a client in the Winnipeg region. it's hard to keep track of all the assessments I've done over the years but that day, something fell out of a tree I was examining and landed on the back of my gloved hand.
The insect was a jewel beetle and it shimmered a metallic green. I had been using my magnifying glass to examine foliage and the insect suddenly loomed enormous on my hand. Startled, I shook it off and it landed somewhere on the ground. I still recall how familiar it looked, possibly from one of the photo plates of insects I have in my library. I knelt down and searched through the grass, hoping to take it in to an entomologist, but I was unable to find it. I'm always going to wonder now what I saw that day.
The emerald ash borer (EAB) was officially discovered in Manitoba last fall (2017). In the years to come, we are going to see change in the landscape as thousands of ash trees are overcome by this insect and will begin to die. Our cold winters will have little effect on reducing EAB populations since the insect has adjusted quite well to life in Moscow, Russia.
Since EAB is an invasive species, it has few natural enemies in our part of the world and populations will quickly rise to damaging levels. All ash trees are susceptible and since the insect is airborne it can easily spread outside of quarantined areas. Ash trees under stress will be the first to become infested and all ash within an area eventually succumb to the infestation within ten years. One only has to travel through southern Ontario to get an idea of the devastation about to occur.
Trunk injections with systemic insecticides provide high levels of protection against wood boring insects and are a viable option for high value trees located on residential and commercial properties. Systemic insecticides are incorporated entirely within the tree's vascular system and are not carried away by wind or rain. Trunk injections must be performed by an ISA Certified Arborist licensed to apply tree injections. Shelemy Arborist Services uses an insecticide developed in Canada by the Canadian Forest Service. Azadirachtin is a biologically based insecticide (from the neem tree) that provides three years of protection against EAB. Treatment costs vary based on tree size, but generally range between $300 to $500 per tree. Trees treated with trunk injections may also benefit from professionally applied root zone fertilizer injection to encourage healthy vigor and reduce environmental stress.