How To Get Rid Of Carpenter Bees

Getting rid of carpenter bees requires a combination of prevention, deterrence, and, in some cases, direct extermination. These bees are solitary wood-boring insects that excavate tunnels in untreated or weathered wood to lay their eggs. While they are important pollinators, they can cause structural damage over time. Here’s how to eliminate and prevent carpenter bee infestations:

Identify the Problem

Carpenter bees resemble bumblebees but have shiny, black, hairless abdomens. You’ll often see:

Round, smooth holes about ½ inch in diameter in wood (usually in eaves, fascia boards, decks, railings, fences, or wooden furniture).
Sawdust beneath holes or staining from bee excrement.
Males hovering near nesting sites (they’re territorial but don’t sting).
Females boring into wood (they can sting if provoked).

Learn more: Carpenter Bees vs Bumblebees

Apply a Direct Treatment to Active Holes

For active infestations, treat the tunnels directly:

Dust Insecticides (Most Effective)

Use a residual insecticide dust like:

Tempo Dust (cyfluthrin)
Delta Dust (deltamethrin)
Drione Dust (silica + pyrethrins)

How to apply:

Treat at night or early morning when bees are less active.
Use a hand duster to puff dust into each hole. One or two puffs per hole is sufficient.
Don’t plug the holes right away; allow bees to contact the dust and spread it throughout the tunnel system. Wait 3–5 days before sealing.

Seal and Repair Tunnels

After treatment:

Use wood putty, caulk, or dowel plugs to seal the entry holes.
Sand and repaint the surface to deter reinfestation.
Replace any severely damaged wood.

Apply Preventive Measures

Paint or Stain Wood

Carpenter bees prefer bare or weathered wood. Painting or sealing wood can discourage nesting.

Oil-based paints are more effective than stains.
Apply regularly to maintain protection.

Install Physical Barriers

Use aluminum flashing, screening, or vinyl trim on frequently targeted areas like eaves, fascia, and soffits.

Use Repellents and Natural Deterrents

While not 100% foolproof, the following can help:

Citrus oil sprays: Boil citrus peels in water, cool, strain, and spray on wood surfaces.
Essential oils: Mix tea tree, lavender, or peppermint oil with water and spray in areas of activity.
Bee deterrent products: Commercial bee repellents can be used in susceptible zones.

Learn more: Spraying for Carpenter Bees

Install Carpenter Bee Traps

Place traps near existing or previous nesting areas. These mimic entry holes and capture bees in a chamber they can’t escape. Use them alongside other methods, not as a standalone solution.

Learn more: Trapping Carpenter Bees

Call a Professional (When Necessary)

If the infestation is widespread, if bees are inside wall voids, or if you are dealing with repeat problems despite preventive efforts, hire a licensed pest control professional. They’ll use stronger tools, access hard-to-reach areas, and provide long-term exclusion advice.

Carpenter bees can return to the same nesting sites year after year, often expanding existing tunnels. That’s why it’s critical to combine direct treatment, physical exclusion, and preventive maintenance. Stay vigilant, especially in the spring when bees become active.