DanielPages Blog

The Emerald Ash borer, or EAB, is a small green beetle native to Asia that has been inadvertently brought to the United States.  Because of the way the larvae feed on Ash trees, the host tree will die within a few years of infestation.  If you have an Ash tree on your property, there is hope.  Some chemical treatments have been shown to be very effective against the beetle.  For trees smaller than 15″ diameter at breast height (DBH), you can treat your tree yourself using off the shelf options from the hardware store or garden center and get good results.  The two most popular active ingredients in homeowner treatments are imidacloprid and dinotefuran.  Dinotefuran has the advantage of moving through the tree’s vascular system much faster than imidacloprid.

If you decide to go with a DIY imidacloprid treatment, consider the following:

• Use soil drench treatments only on very small trees.  Make sure you pull away all mulch so that the treatment goes on to bare soil.
• For trees larger than a few inches DBH, consider imidacloprid injections instead of a soil drench.
• Perform soil drenches early to mid spring, and injections mid to late spring.
• Applying fertilizer annually helps the tree heal and stay healthy.

If you decide to go with a DIY dinotefuran treatment, consider the following:

• Use soil applied treatments only on small trees.  Make sure you pull away all mulch so that the treatment goes on to bare soil.
• For larger trees, consider using a bark applied treatment.
• Dinotefuran should be applied mid to late spring.
• Applying fertilizer annually helps the tree heal and stay healthy.

The best option is called emamectin benzoate, or TREE-äge.  It will work on Ash trees of all sizes, and is over 99% effective at killing the EAB in Ash trees (much higher than any other treatment).  Another plus is that it only needs to be applied every other year, whereas imidacloprid and dinotefuran need to be applied every year.  The only downside is that it must be applied by a tree care professional.  That generally makes it the most expensive treatment option.  If you are serious about saving your Ash tree, I would highly recommend TREE-äge.  I also recommend that you get competing quotes from multiple tree care companies to be sure you are getting the best value.

If you decide that you do not want to spend the money on treating your Ash tree, it is important that you remove it when the EAB gets close to your area.  Untreated trees provide a breeding ground for the EAB and worsen the problem.  Not to mention that once the tree dies, it will become a safety hazard.

-Daniel