Which option is NOT a sign of Emerald Ash Borer infestation?

• A. D-shaped exit holes in the bark
• B. Absence of canopy thinning
• C. Serpentine larval galleries beneath the bark
• D. Increased woodpecker activity

Answer: (B)

Recognizing signs of Emerald Ash Borer infestation is about knowing what a tree typically shows as the beetles attack it: exit holes made by adults, galleries traced under the bark by larvae, and increased woodpecker activity as birds probe for the larvae. D-shaped exit holes are a classic external sign where the beetles emerge. Beneath the bark, the larvae carve serpentine, winding galleries that disrupt the tree’s nutrient flow. Woodpeckers often respond by foraging more around infested trees, leaving bark missing in patches and other feeding signs. As the tree weakens, its crown usually thins noticeably due to leaf loss and dieback.

The option describing an absence of canopy thinning is not a sign of infestation. If the canopy remains full and shows no thinning, that runs contrary to what happens as EAB infests a tree; thinning is a common indicator of decline from the beetle’s activity.