Looking for EAB

Fri. Apr. 26, 2019

Click below to listen to my 2 min. Garden Bite radio show:  Looking for EAB

While this ridiculously cold Winter seems like it should have killed some bad bugs, I’ve heard from bug specialists, that’s not the case.  Bummer.

March 3, 2019

University of MN Ext. Entomologist, Jeffrey Hahn, DOES say, that now is a great time to examine your ash trees for evidence of emerald ash borer (EAB).

Emerald Ash Borer

It may seem early, that maybe you need the leaves on the trees to check the canopy, but Hahn says that’s not a good indicator of whether your ash is infested.  He says, in fact, having a leafless tree makes it easier to search for EAB clues. So what do you look for?

Symptoms include woodpecker pecking.  EAB larvae is a favorite snack.

EAB larvae by Jeff Hahn

Hahn says, although woodpeckers eat other insects, their presence on an ash tree is definitely a red flag.  

Another sure symptom is small, 1/8th inch sized D-shaped exit holes. Unfortunately, they’re easy to overlook because of their size.  Also, EAB starts infesting trees at the top of the canopy and then work their way down, so by the time you see those holes, your tree’s been infected for a while.  

EAB d-shape exit hole by Jeff Hahn

Another definitive symptom is S-shaped squiggles, (my unofficial term) under the bark. Obviously you can’t see these unless you take the bark off.


EAB tunneling by Jeff Hahn