Why Carpenter Bees Drill Perfectly Round Holes

by IMT Support

Understanding the Problem Before It Gets Worse

If you've noticed small, smooth, perfectly round holes in the wood around your home, you might be dealing with carpenter bees. These bees don’t chew on wood randomly—they drill with purpose.

At Bees N Things, we help homeowners across the U.S. with carpenter bee traps and solutions that are proven to work. Understanding why these bees drill such precise holes is the first step toward preventing long-term damage.

Why Are the Holes So Perfectly Round?

Carpenter bees don’t just chew wood—they bore into it using their powerful mandibles. The result is a nearly perfect ½-inch diameter hole that leads into a long tunnel system.

Here’s why the holes are so precise:

  • Efficiency: A round hole takes the least effort and offers a structurally sound entrance.

  • Biology: The shape of the bee’s body and the way it chews naturally forms a circular hole.

  • Reusability: These holes serve as long-term nesting sites and are often reused or expanded year after year.

Unlike termites, carpenter bees don’t eat wood—they tunnel into it to lay their eggs. So every one of those neat little holes is the start of a nursery and storage space deep inside your wooden structure.

Where You’ll Find These Holes

Keep an eye on any untreated or exposed wood around your home, especially in spring. Common spots include:

What Happens Inside the Hole?

That single round hole usually leads to a main tunnel that can stretch 6–10 inches, with several offshoots where the female lays her eggs. These tunnels are hard to spot unless you cut open the wood—but they’re what causes the real damage.

Over time, bees return to the same holes, extend the tunnels, or create new ones nearby. What starts as one hole can quickly become a network of internal damage.

Are These Holes a Big Deal?

Yes. While a single hole might seem minor, multiple generations of carpenter bees can cause serious structural issues. Left untreated, the damage compounds:

  • Tunnels weaken the wood from the inside

  • Woodpeckers may show up to eat the larvae, making the holes worse

  • Moisture and rot can enter through the exposed areas

The good news? You can stop it before it spreads.

How to Stop Carpenter Bees from Drilling

At Bees N Things, we believe prevention is easier than repairs. That’s why we recommend a combination of carpenter bee traps and proactive solutions to keep them from coming back. If you already have carpenter bee damage use our Bee Dams to clog the holes.

Here’s What You Can Do:

1. Install Carpenter Bee Traps
Hang traps early in the season near past activity. Our USA-made traps mimic nesting holes and lure the bees in—no chemicals, no mess.

2. Fill and Seal Old Holes
Once you’re sure the bees are gone (usually late fall), plug the holes with dowels and seal them with wood filler or paint to deter reuse.

Why Our Traps Work Better

Bees N Things offers the best carpenter bee traps in the United States, and we’re proud of it. Here’s why our traps stand out:

  • Made from durable, weather-resistant wood

  • Specifically designed to attract carpenter bees (not just any insect)

  • Easy to install and reuse every season

Thousands of customers trust our traps because they actually work—and we’re here to help every step of the way.

What to Expect Next

If you've already spotted those perfect round holes, you're not alone. But the longer you wait, the more bees—and damage—you'll have to deal with come spring.

Here’s what we recommend:

  • Inspect your property for signs of activity

  • Install traps before the next warm season

  • Check out our full line of carpenter bee solutions to stop damage at the source

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