Woodpeckers help and hurt trees. They help by devouring insects that injure trees, including ants, caterpillars and borers. They hurt trees because their pecking damages tree bark, leaving possible points of entry for disease. If the woodpecker pecking is extensive — for instance, wrapping entirely around a stem — it can girdle part of the tree, cutting off the flow of sap and killing the portion above the damage.

Plus, birds have a habit of building nests in inconvenient places. Find out when and how you can move a bird nest if needed.

Why There’s Pecking

So, why do woodpeckers peck? The primary reason is eating. Sapsuckers peck small holes in search of tree sap. Other kinds of woodpeckers are searching for insects like ants, wood borers and bark lice. Often these insects are afflicting a tree that is already stressed from other factors. It may be diseased and dying, or dead and rotting. In effect, the damage has already been done. When foraging for insects, woodpeckers drill at different depths. They may leave tiny rows of holes on living trees or huge craters in dead and rotting trees. If you have a dead tree, here’s how to cut it down safely.

Other Reasons for Pecking

In the western region of the U.S., acorn woodpeckers peck away to make small cavities to store acorns for later use. These granaries, as they’re called, can contain hundreds or even thousands of small acorn-size cavities, which are used repeatedly to store the seeds.

Woodpeckers may also be excavating nesting and rooting cavities, making holes that are only slightly larger than the woodpecker itself and not a serious threat to healthy trees.

And finally, woodpeckers hammer away at a variety of surfaces — everything from wooden siding to metal gutters, downspouts and roof vents — to communicate with each other. The rapid and loud hammering, called drumming, is done by both sexes and can serve any purpose from proclaiming a territory to calling for a mate. Here’s how to keep birds from becoming pests.

Preventive Measures

One way to protect trees is to wrap trunks in burlap or mesh to discourage pecking. You can also hang reflective steamers or tape, strips of aluminum foil or old CDs/DVDs on and near the tree trunk because woodpeckers (and other birds) are scared off by the dancing light and reflections.  Check out what else you can use aluminum foil for.

Pick up some reflective foil tape on Amazon.

A short-term solution is to station a plastic owl nearby and reposition it every few days so woodpeckers don’t get used to it. Or try distracting them from foraging on the tree with a tempting slab of suet placed elsewhere. Here’s more tips for how to deter woodpeckers.

The Real Threat

Although tree damage is a concern, many homeowners are more worried about woodpecker damage to their house, particularly those with cedar siding. Because woodpeckers are a protected species and cannot be legally harmed, your best bet is to use a preventive measure or an exclusionary tactic, such as hanging up bird netting. Buy some bird netting on Amazon.

If you hear drumming on your house, inspect the siding and eaves and immediately cover any damage with lightweight sheet metal or hardware cloth to discourage a repeat visit. You can learn more about woodpeckers here.

Plus, make sure your new tree gets off to a good start with these tree-planting tips.