If the emerald ash borer continues to spread unabated, it poses a major economic threat, but that does not mean you have to cut down all your ash trees at the first sign of trouble. In fact, when dealing with emerald ash borer, you should not remove or do any tree pruning until late fall because the borer is most active during the summer and cutting down infected trees will only speed up the spread of the EAB. But cutting down trees in fall when the emerald ash borer is less active will limit the spread of the insects.
Saving the Ash Trees in Your Garden
If you have a few ash trees in your garden or a couple of large shade trees and are worried about them being attacked by emerald ash borer, you do have a number of options. Preventive treatments are the most effective in the fight against EAB but if you detect an infestation early, you might be able to treat your tree and prevent further damage, giving the tree a chance to recover and ultimately survive.
One preventive treatment is a drench that you can apply to your trees, but it is only effective on smaller trees with a trunk diameter of less than 8 inches and the treatment is expensive. Another emerald ash borer treatment that can potentially keep your trees alive are injections that are administered by a professional arborist. The trees will have to receive these injections for as long as they are alive but saving a whole lot of trees in this way, however, is not economically viable.
Insecticide treatments for emerald ash borer are not needed for ash trees that are further than 15 miles from a confirmed EAB infested site. Even within the 15-mile radius, not all ash trees can be treated with insecticide because it is expensive, and this form of treatment is typically only used for high-value trees. High-value ash trees are generally healthy trees that add to the value of your property, play an integral role in your landscaping, reduce your energy costs by shading your home or provide environmental benefits.