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Keeping Emerald Ash Borers at Bay in Denver


Emerald Ash Borer or (EAB), a non-native insect, has infested the ash trees of Boulder, Colorado.   Unfortunately, these pests have no predators to keep their numbers in check. EABs infest and can kill ash trees which make up about 15% of trees in Colorado’s urban forest. The Denver metro area alone has an estimated 1.45 million ash trees.
The signs of an infested ash tree are:
  • Sparse leaves or branches in the upper part of the tree
  • New sprouts on the lower branches or trunk
  • Vertical splits in the bark
  • Winding s-shaped tunnels under the bark where the larvae feed on the tree’s tissues
  • D-shaped exit holes that are about 1/8 inch wide
  • Increased woodpecker activity
American Arbor Care wants to do everything we can to keep the Boulder infestation from spreading to Denver as EABs are hard to notice when first introduced to a new territory. Since detected in southern Michigan in 2002, they have spread rapidly to 22 states. Colorado is the most recent state to have detected EAB and it’s reasonable to predict them spreading beyond Boulder if not contained. To prevent your ash tree from being infested and put in danger of dying, call a certified professional arborist to administer a preventative injection.