"My tree has little shallow holes all around it in several areas, about pencil-eraser depth. They are in a circular pattern for the most part. Any ideas?"
If by a “circular pattern” you mean the small holes in your tree seem to encircle the trunk, and if those holes are evenly spaced (as if in a pattern, as opposed to scattered all over, helter-skelter), a woodpecker may be responsible. And if a woodpecker is, indeed, the culprit, you don’t need to take any action — it should be fine. Otherwise, I’d say “borers” — and recommend insecticide.