Woodpecker Holes in Your Tree: Nuisance or Warning Sign?

A woodpecker working on a tree in your yard is either completely harmless or a useful warning, and the difference is written in the pattern of holes. Homeowners usually worry about the bird. In most cases the bird is the messenger.

Woodpeckers hammer wood for three reasons: to find insects, to drum for territory, and in the case of sapsuckers, to drink sap. Each leaves a distinct signature on the bark.

Reading the Hole Pattern

Neat horizontal rows of small, evenly spaced holes, often in bands around the trunk or a large limb, are sapsucker wells. The bird drills them to get at sap and returns to maintain them, so the rows expand over a season.

Irregular, scattered holes of varying size, especially where bark is flaking off and the wood beneath looks chewed, mean the bird is hunting insects. Large oval excavations are a nesting cavity, which means the wood is soft enough to dig into.

When the Bird Is Telling You Something

Insect-hunting damage is worth investigating. Woodpeckers are efficient at locating wood-boring beetle larvae and carpenter ants, and heavy feeding activity concentrated on one limb often means there is a population under the bark and the wood is already compromised.

Nesting cavities carry a similar message. A bird excavating a hole in a live tree is usually working in decayed or softened wood, which says something about the structural condition of that stem.

Sapsucker Wells and Real Harm

Sapsucker feeding is usually cosmetic on a healthy tree. The wells scar the bark and can look alarming, but a vigorous tree compartmentalizes them without difficulty.

Heavy, repeated banding on the same stem is a different matter, because enough wells in a tight band can girdle a branch, and the wounds provide entry points for decay fungi and disease. Species that get hammered year after year, including birch and mountain ash here, deserve a closer look.

Deterrents That Actually Help

Woodpeckers are protected, so the approach is deterrence rather than removal. Reflective tape, hanging mylar strips, or lightweight netting held away from the trunk can break the habit if deployed as soon as the activity starts.

Wrapping the affected section with burlap or hardware cloth during the active period protects the bark directly. Deterrents work best early; once a bird has established a routine on a particular tree it is much harder to redirect.

Do Not Fill or Seal the Holes

The instinct is to plug the holes with filler or paint them over. Do not. Sealants trap moisture against the wood, interfere with the tree's natural compartmentalization, and can accelerate decay rather than prevent it.

Leave the wounds open, keep the tree healthy, and let it wall the damage off, which is what trees are actually good at.

When to Get the Tree Looked At

Get an assessment if the holes are concentrated on one limb, if bark is loose or flaking around them, if you see sawdust-like frass, or if a cavity has been excavated in a trunk over something you care about.

The bird is rarely the problem. Aardvark Tree Care can check whether the wood under that activity is sound or whether the tree has an insect or decay issue that needs addressing before a limb comes down.

Neat rows mean sap; scattered ragged holes mean the bird found something living under your bark.