Carpenter Bees Drilling Your Fascia? Here's What to Do

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Carpenter Bee vs Bumblebee

Carpenter bees look almost identical to bumblebees at first glance — fat, fuzzy, slow, loud. The tell:

• Carpenter bee: shiny black abdomen, no fuzz on the back end. Often hovers in one spot.
• Bumblebee: fuzzy yellow-and-black abdomen all the way to the tail.

Carpenter bees are solitary — there's no hive. Each female bores her own tunnel and lays a small number of eggs inside. That's why you see one or two hovering around the deck instead of dozens swarming a single nest.

What They're Doing

In early to mid May in Central PA, female carpenter bees look for unfinished or weathered softwood to bore into — pine, cedar, redwood, cypress. They drill a perfectly round 1/2-inch entrance hole that goes straight in about an inch, then turns 90 degrees and runs along the grain for 4–6 inches. Inside the tunnel they lay eggs in a series of chambers, each provisioned with pollen and sealed with chewed wood pulp.

The male carpenter bee is the one that hovers aggressively in front of the entrance hole defending the territory. He looks scary but he has no stinger — he can't sting you. The female has a stinger but rarely uses it unless physically handled.

How Much Damage Do They Actually Do?

Year 1 of an infestation is mostly cosmetic — small holes you can fill. The real damage comes from two compounding factors:

1. Reuse and expansion. Carpenter bees come back to the same wood year after year and add new tunnels branching off the old ones. A 5-year-old infestation can have 20+ feet of tunneling inside a single piece of fascia.
2. Woodpeckers. Pileated and downy woodpeckers can hear the carpenter bee larvae chewing inside the wood and will tear the fascia apart to eat them. The bee damage is small. The woodpecker damage is large and obvious.

Common targets in Central PA: cedar fascia and rake boards, redwood deck rails and pergolas, soffits, log home siding, garden sheds with weathered trim, and exposed barn beams.

What Works

1. Treat the Entrance Holes

An insecticide dust pushed into each entrance hole in May coats the female as she enters and exits. She carries it into the tunnel and onto the eggs. One treatment typically ends the activity in that tunnel. Liquid sprays don't penetrate as effectively as dust.

2. Seal the Holes — After Treatment

Once the tunnel is treated and the activity has stopped (usually 1–2 weeks later), seal each entrance hole with wood putty or a wood dowel set in glue. This blocks reuse next year and prevents woodpecker discovery. Don't seal the hole before treatment — trapping live bees inside often makes them chew a new exit elsewhere.

3. Paint or Stain the Wood

Carpenter bees strongly prefer raw, weathered, or stained-but-not-painted wood. They mostly avoid painted surfaces. The long-term fix for a chronically attacked fascia or deck rail is paint, not stain. For natural-finish cedar, applications of a heavy oil sealer help but aren't as effective.

4. Replace Badly Damaged Wood With a Hard or Composite Substitute

For fascia that's been chewed for years, replacing with PVC trim, cement board, or a hardwood like white oak ends the cycle. Carpenter bees don't drill these materials.

What Doesn't Work

• Spraying the bees in the air. They keep coming back. The colony is in the tunnel, not in the air.
• "Carpenter bee traps" alone. They catch some females, but rarely enough to stop the damage on an active infestation. Use them as a supplement, not a treatment.
• Sealing holes without treating. The bees chew new exits — often in worse locations.
• Treating in fall. The adults are gone. Only over-wintering larvae remain, and they're well past easy treatment.

Bee-Safety Note

We work hard to make sure honey bees and bumblebees aren't impacted by carpenter bee treatment. Hole-by-hole dust application targets only the carpenter bee tunnels — there's no exposure to pollinators on flowers. We don't spray broadly. As a working beekeeper ourselves, this is non-negotiable on every property.

When to Call Us

If you have active holes in fascia, deck rails, or a pergola, May is the window. The longer you wait, the more eggs are laid and the more woodpecker damage compounds. Call or text 717-379-3248 for a free walk-around — we'll count the active tunnels and recommend treatment, sealing, or whether full board replacement is the better long-term play.