Emerald Ash Borer
Emamectin benzoate can be effective, but because the activity of the larval boring prevent even uptake, you can't predict how effectively it will be able to spread throughout the canopy of the tree. Consequently, unless there is very little --or NO-- infestation yet, it is very questionable whether it will save a tree. If you have a valuable specimen tree, it may be worth the expense, but try to start treatments BEFORE infestation.
The emamectin stays in the tree, and because ash are wind pollinated, bees are not impacted.
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