Emerald Ash Borer (EAB) is an invasive beetle that has killed millions of ash trees across the Midwest, and Iowa is no exception. The insect itself is small and rarely seen, but the damage it leaves behind is easier to spot once you know what to look for.
How Emerald Ash Borer Damages Trees
Adult beetles lay eggs on ash bark. When the larvae hatch, they tunnel beneath the bark and feed on the layer that carries water and nutrients through the tree. Over a few seasons, those feeding galleries cut off the tree’s supply lines and the canopy begins to decline from the top down.
Common Signs of EAB Infestation
- Thinning or yellowing leaves in the upper canopy.
- Dieback, with bare branches near the top of the tree.
- D-shaped exit holes about 1/8 inch wide in the bark.
- Vertical bark splits that reveal S-shaped tunnels underneath.
- Heavy woodpecker activity and light patches where bark has been stripped.
- Sprouts at the base or along the trunk as the tree tries to survive.
Is It Really an Ash Tree?
EAB only attacks ash. Ash trees have opposite branching, compound leaves with five to eleven leaflets, and bark with a diamond-shaped ridge pattern on mature trees. If you are not sure what you have, a professional can identify your trees and tell you which ones are at risk.
Treatment or Removal?
Healthy, valuable ash trees with little canopy loss can often be protected with treatment. Trees that have already lost a large part of their canopy, or that are dead, become brittle quickly and can drop limbs without warning. Those trees are usually safer to remove, especially near homes, driveways, and play areas.
Talk to an Emerald Ash Borer Specialist
Arbor One Tree & Landscape helps Okoboji-area homeowners assess ash trees, explain their options, and safely remove trees when it is necessary. Call or text (470) 651-6785 or request a free estimate and we will take a look.
