Which of the following is a classic sign of Emerald Ash Borer infestation?

• A. White powder on the trunk
• B. D-shaped exit holes in the bark
• C. Uniform canopy color
• D. Excessive resin on limbs

Answer: (B)

Emerald Ash Borer is a wood-boring beetle, and the most recognizable field sign is exit holes it creates when adults emerge through the bark. These holes have a distinct D shape—flat on one side with a curved edge—so they look like the letter D. That characteristic hole shape is a reliable clue that ash trees are being attacked by this pest, often visible on the trunk or main limbs. You might also see galleries under the bark or crown decline as the larvae feed and damage the tree, but the D-shaped exit holes are the classic, easiest-to-detect sign. The other options don’t fit EAB patterns: they’re not typical indicators of this infestation and point to different issues or pests.