Crow’s Nest: Emerald Ash Borer arrives

June 20, 2017

By Daniel Barringer, Preserve Manager

Although Chester County and Pike County remain the only two counties in Pennsylvania as of June 14, 2017 where Emerald Ash Borer (EAB) has not yet officially been detected—it’s almost certainly already here.

Photo by Daniel Barringer

Several ash trees at Crow’s Nest Preserve are declining with damage consistent with what I have observed at other preserves where EAB is known to occur. I haven’t seen the insect larva or adult, but ask the woodpeckers—they’re excavating many more holes in ash trees than they normally would.

We’ve removed a few dozen of our ash trees along the roadsides (to prevent them from becoming hazards as they die). We have 200 ash trees total along roads that will have to come down. I also injected ten of our best ash trees with insecticide to protect them from the borer. The infestation is thought to be completely fatal for ash species.

Consider this a Public Service Announcement: if you have ash trees in your yard you need to act now. Have the trees treated for EAB or cut them down. They are going to die, and soon—most trees die within three years of EAB’s arrival. The opportunity to spread the cost out over multiple years is ending quickly. Treating the trees may be a cost effective alternative for homeowners, though it becomes prohibitive at a landscape scale.