How To Stop Carpenter Bees

This comprehensive guide covers everything you need to know: why carpenter bees are attracted to your home, how to deter and remove them, and strategies for long-term prevention.

Understanding Carpenter Bees

Carpenter bees resemble bumblebees but have shiny, hairless abdomens. Unlike termites, they don’t eat wood—they excavate tunnels to lay eggs. Males can be aggressive but lack stingers; females can sting but rarely do unless provoked7.

Why Carpenter Bees Target Your Home

Carpenter bees prefer:

• Unpainted, weathered, or untreated wood (especially softwoods like pine, cedar, cypress, and redwood)

• Wood exposed to sun (under eaves, decks, railings, and siding)

• Cracks, holes, or depressions in wood as starter points for excavation156

Prevention: The Best Defense

1. Paint, Varnish, or Treat Wood

• Painted or varnished wood is far less attractive to carpenter bees than bare wood. Oil-based or polyurethane paints and stains are especially effective barriers12569.

• Maintain coatings regularly—weathering or peeling paint can invite bees back.

• Consider light-colored paints or stains, which are less appealing to carpenter bees7.

2. Use Hardwood or Non-Wood Materials

• Carpenter bees prefer softwoods. If possible, use hardwoods or non-wood alternatives (vinyl, metal, composite) for vulnerable structures167.

3. Seal Cracks and Holes

• Fill all pits, cracks, and old bee holes with caulk, wood putty, or steel wool, then paint or varnish over the repair. Do this in late summer or early fall after bees have emerged, or in early spring before nesting begins1256.

• Carpenter Bee Blocker Kits (stainless steel screens) can be installed in old holes for added protection5.

4. Regular Inspections

• Check wood surfaces each spring for new holes or signs of activity. Early detection allows for prompt action before damage escalates7.

Natural Deterrents and Repellents

1. Citrus and Almond Oil Sprays

• Citrus oil and almond oil are natural repellents. Mix with water and spray onto susceptible wood surfaces every few days in spring and summer18.

• For existing nests, apply oil directly into the holes to encourage bees to relocate18.

2. Noise and Vibration

• Carpenter bees dislike loud noises and vibrations. Hang wind chimes or play music near active nests for a few days to encourage them to leave148.

3. Fake Wasp Nests

• Carpenter bees avoid nesting near wasps. Hang inflated paper bags or commercial fake wasp nests under eaves or in problem areas to deter new nesting1.

Physical and Mechanical Controls

1. Carpenter Bee Traps

• Specially designed traps attract and capture carpenter bees. Hang traps near eaves, decks, and sunny areas where bees are active78.

• For best results, use bait (like bee attractant) and place traps before nesting season begins.

2. Vacuuming

• For new, shallow nests, a strong vacuum with a narrow attachment can sometimes remove adult bees. Seal the hole afterward to prevent re-entry8.

Chemical Controls (When Necessary)

1. Residual Insecticides

• Spray residual insecticides (such as Cyzmic CS, Demon WP, or FenvaStarCap) on vulnerable wood surfaces in early spring and again every 3–4 weeks during nesting season5.

• Focus on undersides of decks, railings, and other shaded, protected wood.

2. Insecticidal Dusts

• Apply insecticidal dust (like Tempo Dust or Delta Dust) directly into carpenter bee holes with a hand duster. This kills bees and larvae inside the tunnels5.

• Wait 24–48 hours after dusting before plugging the holes.

3. Aerosol Sprays

• Wasp, hornet, and bee aerosol sprays can be applied into tunnel entrances and along the length of the hole6.

Repairing and Plugging Carpenter Bee Holes

• Plug holes only after confirming bees have left or been eliminated. If sealed too soon, trapped bees may chew new exit holes elsewhere15.

• Use wood putty, caulk, cork, or Carpenter Bee Blocker Kits to seal holes, then paint or varnish over the repair for extra protection156.

• The best time to seal is late summer or early fall, after new bees have emerged156.

Ongoing Maintenance and Monitoring

• Reapply protective coatings every 1–2 years, especially in high-risk areas.

• Inspect and repair any new holes or damage promptly.

• Relocate or replace wooden items (like birdhouses or outdoor furniture) that are attracting bees, or switch to non-wood alternatives7.

Are Carpenter Bees Dangerous?

• Male carpenter bees cannot sting. Females can, but rarely do unless provoked or handled7.

• While not aggressive, their tunneling can cause significant structural damage over time.

Summary Table: Carpenter Bee Control and Prevention

Eco-Friendly Perspective

Carpenter bees are valuable pollinators. Whenever possible, prioritize prevention and non-lethal deterrents. Reserve chemical controls for severe infestations or when structural damage is significant, and always follow label instructions to minimize harm to beneficial insects and the environment15678.

Conclusion

Stopping carpenter bees requires a combination of prevention, deterrence, and, if necessary, targeted removal. By painting and maintaining wood, sealing cracks and holes, using natural repellents and traps, and applying insecticides responsibly, you can protect your property while preserving these important pollinators. Regular inspections and prompt action are your best defenses—so start early each spring, and enjoy a bee-friendly, damage-free home and garden.