---
title: "What Is D-shaped exit hole? Stump Grinding Glossary"
description: "A D-shaped exit hole is the small hole an adult emerald ash borer leaves in the bark of an ash tree when it emerges from the wood."
url: https://cincystump.multisites.ai/glossary/d-shaped-exit-hole
publisher: Cincinnati Stump Grinding
phone: +1-513-587-6772
quote: https://cincystump.multisites.ai/contact
---

Pests

# D-shaped exit hole

A D-shaped exit hole is the small hole an adult emerald ash borer leaves in the bark of an ash tree when it emerges from the wood.

USDA APHIS describes the life cycle this way: emerald ash borer larvae feed on the inner bark and phloem. They pupate in winter, then emerge as adults in spring and leave D-shaped exit holes. Ohio State's BYGL newsletter says adults emerge in early summer, so timing can vary by source and year.

The hole is one sign among several. APHIS also lists dead branches in the upper part of the tree, excess branching on the trunk and vertical cracks in the bark. More woodpecker activity can point to larvae under the bark. This page cannot confirm any tree is infested. APHIS asks people who think they see the pest to use its report form. See [emerald ash borer](https://cincystump.multisites.ai/glossary/emerald-ash-borer) and [ash tree](https://cincystump.multisites.ai/glossary/ash-tree) for background.

## Related terms

-   [Emerald ash borer](https://cincystump.multisites.ai/glossary/emerald-ash-borer)
-   [Ash tree](https://cincystump.multisites.ai/glossary/ash-tree)
-   [Bush ash](https://cincystump.multisites.ai/glossary/bush-ash)
-   [Invasive plant](https://cincystump.multisites.ai/glossary/invasive-plant)

## Sources

1.  [USDA APHIS: Emerald Ash Borer](https://www.aphis.usda.gov/plant-pests-diseases/eab)
2.  [USDA APHIS: Emerald Ash Borer](https://www.aphis.usda.gov/plant-pests-diseases/eab)