How To Get Rid Of Carpenter Bees With WD-40

David Floyd:

David Floyd has 20 years of experience working as a pest control technician as well as running his own pest control company. David is Quality Pro certified and is a certified Structural Pest Control Operator in the state of North Carolina, and the owner of NCPestControlExperts pest control company.

Last Updated: December 19th, 2022: If you’re dealing with a carpenter bee infestation it can be a nerve-wracking time as well as a destructive time. Carpenter bees are excellent drillers and build homes in wood, which can mean bad news for your home! That being said, carpenter bees do play an important part in our ecosystem, which means you should immediately resort to killing carpenter bees. But is there another option? In this guide, we’ll be testing out how effective it is, and how to get rid of carpenter bees with WD-40!

how to get rid of carpenter bees with wd-40

WD-40 is a common, thin oil spray that is famous for its many uses. It is present in many homes because it serves many household functions. WD-40 is effective in stain removal, lubricating metal parts, and thawing frosted surfaces, but can it actually be used to get rid of carpenter bees?

Hence, it is also used to get rid of carpenter bees. In this article, we will explore the effectiveness of WD-40 on carpenter bees, and how it gets rid of them. We also have a bigger guide on how to naturally get rid of carpenter bees.

Does WD40 Kill Carpenter Bees?

WD40 will kill carpenter bees and just about any other insect if they come into contact with enough WD40 and for a long enough time period. WD40 contains a collection of mineral spirits which is toxic to insects and can kill most insects within around 5 minutes. So if you’re wondering will wd-40 kill carpenter bees, the answer is yes!

How To Get Rid Of Carpenter Bees With WD40!

Spray WD-40 directly into the carpenter bee holes using the long nozzle to fill the entire carpenter bee nest or spray on the insect directly. Once sprayed, the carpenter bees should begin to start dying within a few minutes. After a day or two if you are still noticing carpenter bees, you should repeat the treatment until there are no more carpenter bees.

To be safe, don’t ever apply the spray near an open flame, and don’t ingest or spray the liquid into your eyes.

using WD-40 for carpenter bees

Killing Carpenter Bees With WD-40 Video Tutorial

If you’re someone who likes videos rather than blogs, we have you covered! Check out our video tutorial!

What is WD-40?

WD-40 is a brand name for a water-displacing spray product. It is an oily substance that has very low viscosity and acts as a lubricant and penetrant.  WD-40 is petroleum-based and contains mineral oil, carbon dioxide, and aliphatic hydrocarbons. Though it lubricates rusty metal parts, it leaves little residue when applied. Due to this volatility, WD-40  should not replace an actual lubricant.

carpenter bees wd40

WD-40 also acts as a cleaner and adhesive remover. It prevents rust, frost, and corrosion from metal tools.  As a result of this versatility, it is popular in various homes.

WD-40 As a Makeshift Pesticide

WD-40 is an oil-based product that is capable of killing carpenter bees and other insect pests.  The mineral oil and hydrocarbons contained in WD-40 are toxic to insects. When it comes in contact with carpenter bees, it interferes with their respiratory system. This works by obstructing the free flow of oxygen and shutting off the air holes (spiracles) of the bee. This results in the blocking of the trachea and the death of the bee by asphyxiation.

The mineral oil contained in WD-40 can also kill carpenter bee eggs laid inside the holes on the wood. WD-40 can form a thin oil layer on the exterior of the egg. Hence, ceasing the exchange of gasses between the egg and its surrounding. WD-40 can act as a poison by interfering with the bee’s metabolism and causing a breakdown of its systems.

WD-40 As a Pest Repellent

WD-40 can also repel carpenter bees and other insect pests from attacking surfaces. Though, as light oil, it is volatile and leaves very little residue. Hence, it may not be very effective as a repellent for an extended period. Still, it can be effective as an insecticide.

Carpenter bees are sensitive to smell, using this sense to locate nectar-producing flowers. Strong-smelling substances like varnish, paint, or WD-40 can disrupt their olfactory senses. Applying these substances on wood surfaces can repel carpenter bees from making nests around your home. Deterring carpenter bees with wd 40 is a good way to get rid of carpenter bees without having to kill them.

How to Apply WD-40 To Carpenter Bee Nests

1. Find and identify infested regions in wood

Nest holes made by carpenter bees are almost round in shape and about a half-inch in diameter. Softwood such as cedar, pine, oak, and redwood is the best nesting choice for carpenter bees. Also, they attack wooden structures such as doorposts, railings, roof eaves, and decks. You may also find carpenter bees infesting unpainted or untreated wood. Observe carpenter bees hovering around your structures and inspect any hole you find.

2. Insert the WD-40 extension tube into the carpenter bee hole

The aerosol can of the WD-40 comes with a straw-like extension used to apply the spray in tiny areas. Stick the extension into the hole, as deep as it can go, and spray the WD-40. Spray for at least 10-20 seconds to coat the inner holes with WD-40. Foamy WD-40 will seep out through the hole, as the pressure created from the tiny hole will push excess of it out. Make sure to clean up any spilled WD-40 liquid on the ground or any other non-wood surface.

The evenings are best to do this treatment because the adult bee is most likely to be resting in the nest hole.

3. Plug Nest Holes

Spraying the nest holes with WD-40 and plugging it immediately will limit airflow in the nest. then, speed up the killing of the bees. Use wood putty or caulking clay to cover the hole after spraying. Read our guide on repairing carpenter bee damage!

Using WD-40 to Prevent and Repel Carpenter Bees

1. Identify Pre-Existing Carpenter Bee Holes

Look out for holes and crevices in your wood structures susceptible to attack. Make sure to cover with small wood dowels, caulking, or wood putty.

2. Apply WD-40 On Unstained or Untreated Wooden Surfaces

WD-40 can repel carpenter bees from infesting wood. You can also use it to prevent other insect pests from invading your wooden surfaces. Paint or stain your wooden surfaces to make them unfavorable for carpenter bees.

Safety Procedures:

WD-40 is a petroleum-based product that may be corrosive and may cause allergies. So you should take great care when handling the product. Put on safety goggles and hand gloves to prevent droplets from getting into your eyes or on your hands. You can also put on a face mask to avoid inhaling it. Make sure not to spray close to an open flame,  WD-40 is flammable and may cause fires.

Adverse Effects of WD-40 on the Environment

Petroleum-based products—including WD-40—are unsafe for the environment because they are non-biodegradable. WD-40 contains carbon dioxide which is a greenhouse gas that depletes the ozone layer. It is toxic to carpenter bees and other insects and can kill them on contact.

Instead of killing carpenter bees, you can fend them off with repellents. You can also use live traps to capture them. You can also set bait wood, for the bees to exploit, rather than your wood structures.

Final Thoughts On Carpenter Bees and WD-40

One of the effective ways to get rid of carpenter bees is by using WD-40. As a popular petroleum-based lubricant, WD-40 is toxic to carpenter bees. It has constituents that can repel or cause them to die off. Spray it in infested holes and cover them to kill the bees and prevent further attack. Also, make sure to carry out safety precautions before use.

I hope you’ve enjoyed our guide on how to get rid of carpenter bees with WD-40, and I hope it is effective for your carpenter bee infestation!


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