You might call the emerald ash borer (EAB) the invisible killer. That’s because they spend most of their life inside your stately ash trees. When the adults finally do emerge, they ‘re smaller than a penny and only live long enough to mate and start the next generation on its path of destruction.
High up in the tree the females carve out indentations in the bark of the tree and deposit one egg in each. Each female can deposit 60 to 100 eggs. They hatch in about a week and the youngsters immediately begin boring galleries into the tree’s phloem, where they eat the food the tree has made through photosynthesis. The EAB starts its destruction at the top of the tree, which is why trees die from the top down.
With treatment, that beautiful ash tree growing in your yard can fend off this tiny attacker. Without treatment, it’s doomed. Unlike some insects, the EAB isn’t drawn to weak or distressed trees. They like them all, as long as they’re ash trees. Granted, it would be cost prohibitive to treat a forest of ash trees but it’s a very good investment to treat that specimen in your yard, and you can have it treated for decades for the cost of removing and replacing it after it succumbs to the EAB.
We have looked into all of the control products on the market and have found only one that we consider to be truly effective. This product is injected directly into the tree trunk near the base. Trees that haven’t been attacked by the EAB only need one treatment every two years. Control may be achieved on trees that have been attacked but only if the destruction is limited to a quarter to one third of the tree. These trees have to be treated annually.
The product we use can only be applied by New York State Certified Pesticide Applicators. I wouldn’t apply anything else to my own trees. It’s just not strong enough. Ash trees are beautiful trees that deserve all the help we can give them to survive.