Ash leaves are somewhat unique since they have several green leaflets per leaf stem, usually seven. The leaflets are located directly across from each other with one at the end.
Emerald Ash Borer
The Emerald Ash Borer is an exotic beetle from Asia. Though small (approximately 1/2 an inch), it can fly up to a mile from where it emerges.
D-Shaped Exit Holes
D-shaped exit holes can be found on trees where the adult beetles emerged. A tree with these holes has been infested for at least one year. They will be present on the branches and the trunk.
“Suckers,” or new sprouts, may develop around the bottom of the main trunk of an infested tree. They can grow until they are 2 to 3 inches in diameter and are again attacked by the emerald ash borer.
Tree canopy will begin thinning and branches will die. First there will be yellowing of the leaves, then dead branches. The thinning will begin at the top third of the tree, then spread over time. Usually, a tree will live two to four years after thinning at the top of the tree occurs.