Emerald Ash Borer in Waukesha County: Treat or Remove Your Ash Tree?
How to tell if your ash tree is infested with emerald ash borer, when treatment makes sense, and when removal is the safer call.
Emerald ash borer (EAB) has killed huge numbers of ash trees across southeast Wisconsin. If you still have a healthy ash in your yard, you have a real decision to make: protect it, or plan its removal before it becomes a hazard.
Signs your ash tree is infested
- Thinning canopy, starting at the top of the tree
- Vertical bark splits, and woodpecker damage that strips bark (“blonding”)
- Small D-shaped exit holes in the bark
- Shoots sprouting from the trunk or base
When treatment makes sense
A common rule of thumb from extension specialists: a valuable ash with less than about 30% canopy loss is often worth treating. Trunk injections, applied by a certified professional, can protect a tree for a couple of years per treatment. Treatment is an ongoing cost, so it makes the most sense for large, healthy, well-placed shade trees.
When removal is the right call
Once an ash is dead or heavily declining, it dries out and becomes brittle quickly. Dead ash is unpredictable to climb and fell, so removal gets more dangerous, and often more expensive, the longer you wait. If the tree is near your house, driveway, or power lines, don’t put it off.
Get it looked at
An arborist can tell you in a single visit whether your tree is a candidate for treatment or should come down. Call one of the local pros featured below to have it looked at.