While these beetles could be considered “pretty” with their iridescent colors, they’re actually quite harmful to the ash trees they like to inhabit. Well the beetle itself isn’t the biggest problem. Unfortunately, it’s larval of Emerald Ash Borer that causes the majority of the headaches. The effect these bugs have on ash trees isn’t shown right away. The damage is really done about 3 to 5 years afterward when the tree starts dying off. Here are a few ways to detect if your ash trees are affected and how to treat them.

  • Some symptoms include:
    • S-shaped tunnels in the bark where the larval has been feeding
    • When the beetles become adults D-shaped holes start appearing
    • Woodpeckers will end up damaging the tree quite a bit trying to get to the beetles for a tasty treat. Although they may end up helping eliminate the borer in that tree. The woodpecker might be the lesser of the two evils.
    • There will be noticeable bark splitting or flaking along with upper crown dieback and epicormic branching. When these appear without any help from the tree owner (if there is one) then there’s a good chance the ash tree has these little bugs.
  • There are a few ways to take care of the tree to stop the infestation. These are the three main ones that will help keep the infestation from spreading:
    • For chemical control, a systemic insecticide applied to the soil, the lower tree trunk, and injecting the insecticide directly into the tree can not only help get rid of the borers, but it can help prevent them from showing up to begin with. The branches and foliage can be covered as well.
    • A form of biological control is more difficult because the USDA Forest Service is still figuring out what type of ash trees are resilient to the emerald ash borers. They have discovered a few species of non-stinging wasps located in Asia that can control the emerald ash borers.
    • If the infestation is bad enough then the most extreme, but a permanent way to get rid of these beetles is to remove the tree altogether. Take out the tree, take out the infestation.