Bees are some of the most important pollinators in nature, but what you might not know is that there are tens and tens of thousands of different species around the world. They’re all a little bit different, and one of the most interesting is the carpenter bee…
Sometimes referred to as wood bees or erroneously as bumblebees, these glossy black, pudgy bees are important pollinators, but they’re also fast and voracious drillers of wood. It’s true; that’s how they got the name!
If you have a large population of such bees in your area, you’ll start noticing huge holes pockmarking your fencing, siding, deck, and any other unprotected wood. Not only is it unsightly, but enough repeat visits can damage structural integrity!
The bees are docile and rarely bother people, but you’ve got to protect your possessions and especially your home. Learn how to get rid of these aggravating woodworker bees with 10 surefire methods that I’ll share with you below.
What Attracts These Bees in the First Place?
Carpenter bees are attracted to wood in the first place because, with very few exceptions, that is how they nest to reproduce.
These bees, contrary to popular opinion, do not eat wood; they eat the same things that other bees eat, namely nectar, pollen, and other sweet stuff.
They drill holes into wood using their powerful mandibles and expand these holes into tunnels where they live and lay their eggs to produce the next generation of bees.
They are particularly attracted to softer dead wood, and they especially target wood that is unfinished, weatherworn, cracking, or otherwise easy to chew into.
Carpenter bees work surprisingly quickly, and even though most are solitary they are generally gregarious and sometimes cooperative, meaning multiple bees could start setting up their homes in close proximity to one another.
Quite literally, your fence or deck could soon look like Swiss cheese if you don’t do something!
The bottom line is that if you have any wood structures on or around your home, carpenter bees will target them.
What Kills Carpenter Bees?
The good news is you have tons of options for killing or displacing carpenter bees. They are vulnerable to all the same things that other kinds of bees and other insects are.
Also, considering they are rarely found working together in huge numbers, tackling the nest yourself is much safer than it would be normally and has a much higher chance of success.
Let me share with you some methods that will either kill off the bees or displace them so they leave and try their luck elsewhere.
Swat Lone Bees
I mentioned above that carpenter bees are typically solitary, meaning they don’t live in actual hive structures like honey bees and many wasps do.
It’s entirely normal to find a carpenter bee living in working completely on its own, though it’s just as common to find a few potential suitors buzzing around nearby, or as much as a single generation of bees living and working together in a single warren of tunnels.
Because you’re likely only have a bee or two to deal with, you can go ahead and swat the bee with no risk of major repercussions.
You can use a sturdy fly swatter, but I prefer to use a tennis or badminton racket; it has a much larger contact area, and carpenter bees are so pudgy there’s no chance of them slipping through the opening in the racket.
A few flicks of the wrist and your carpenter bee problem might be a thing of the past. 🙂
Getting Rid of These Bees with Vinegar
You’ve got several effective DIY methods to choose from if you want to carpenter kill bees safely without resorting to poisons.
One of the best and, surprisingly, one of the least known methods is through the use of vinegar. Vinegar is a strong acid that can injure and kill many insects pretty easily.
You can mix up your own vinegar-based bee killer by using equal parts water and vinegar in a spray bottle.
If you notice the bee on a surface, squirt it several times and it will probably die a little bit later. Also, don’t be afraid to squirt the area around the nest and directly into the hole until it is soaked.
A few applications like this and you can completely neutralize a nest.
Dish Soap is Effective Against Bees
Another effective bee killer that can be made in seconds in your own kitchen…
Mixing common liquid dish soap with water to make a strong solution and then loading that in a sprayer will let you go to town on carpenter bees and their nests.
It sounds unusual, because how can soap be harmful, anyway, right?
Well, if you understand a few interesting facts about insect physiology, it all makes sense: insects have an exoskeleton, and that exoskeleton is coated with a waterproof, waxy covering called the cuticle.
This coating is responsible for keeping the exoskeleton in good shape, but more importantly for helping the insect to retain moisture. Dish soap will degrade and eliminate the cuticle, meaning the insect will start to dry out. When that happens, they die.
Same as before, squirt the bee directly with your dish soap solution and spray it all over and into their nest. If you have more than one bee in the nest, it will take several applications.
The great thing about this method is that it is completely safe otherwise, and poses no risk whatsoever to mammals or people.
Use DE to Kill Carpenter Bees
Another great, all-natural insecticide you might try is a diatomaceous earth. This multi-purpose powder is actually made from the ground-up shells of ancient crustaceans, but practically speaking each individual granule is incredibly hard and sharp. This means that it will lacerate the exoskeleton and soft tissues of insects, eventually killing them.
It takes time to work, and you’ll need to get the powder directly into the nest hole and around the nest entrance to make sure carpenter bees get exposed to it, but the stuff is persistent and it will kill the bees sometime after they come into contact with it.
Like the dish soap method above, I really like using DE for this purpose because it’s almost entirely harmless otherwise to people and pets.
It poses a slight inhalation hazard, but so long as you are not wafting tons of stuff into the air while applying it you don’t have anything to worry about.
Insecticidal Dust Will Kill Bees and Prevent Reuse of Nests
Sometimes you need to go with a method that’s a little more decisive, and if that sounds like your situation, you might want to go straight to using a purpose-designed insecticide.
Insecticidal dust is particularly effective against carpenter bees because it will catch the bees as they come and go leaving the nest via that one entrance total. If the bee has any sisters or young inside the nest, they will likewise be affected in time.
You know the drill: apply the powder all around the entrance to the nest and directly into the hole. Make sure you reapply if it gets wet.
Try Liquid Pesticide Sprays
Liquid pesticide sprays are also very effective against carpenter bees, as with most other insects. However, these chemical concoctions do pose a danger to mammals and especially to birds, so you should only use them as a last resort if possible.
You have options here, too: you can simply get a common bee or wasp killer spray that will paralyze and kill on contact almost instantly.
You can also use something like a residual spray which will leave behind a trace poison that will affect the bees over time once they travel over the treated area.
Either works, but if you’re dealing with larger infestations I would recommend the residual spray because you can treat and leave without having to wait around and try to pick off the bee directly.
Boric Acid
Boric acid is another insect killer that has been in use for a very long time, and it tends to have a lower environmental impact than the commercially produced pesticides talked about above. You can get it yourself in a powder format by purchasing common Borax.
It does take time to work, but it is absolutely effective against carpenter bees. As before, just sprinkle it all around the entrance to their nest and directly into the hole and the bees will be affected as they pass by.
Remember to reapply periodically or after it rains until the infestation has ended.
Almond Oil
For whatever reason, carpenter bees absolutely despise almond oil and will flee from it. If you can get yourself some concentrated, real almond essential oil you can apply it directly in and all around holes where carpenter bees are active using a sprayer or a dropper.
Any adult bees in the area should vacate and move on, but make sure you’ve got a follow-up plan for dealing with them if they start building somewhere else nearby. I suppose you could always just keep spraying the almond oil and chase them off eventually.
Citrus Oils Are Effective Bee Repellents, Too
Another all-natural and completely safe bee repellent, citrus oils are one of nature’s ways of protecting fruit from various insects, bees included. It makes sense then that bees will also fly away from orange, grapefruit, lemon, and lime oils.
Just as we did with the almond oil above, use a dropper or sprayer to apply directly into and around the nest hole.
Pretty soon your bees should go elsewhere and hopefully stop tearing up your fence or deck. As a bonus, this method will make your outdoor spaces smell absolutely amazing!
Kill Carpenter Bees with WD-40
No, I am not kidding. Is there anything you can’t fix with this trusty blue can? WD-40 is a good, improvised insect killer because it has a nice one-two punch: it has hydrocarbons and various compounds which are directly toxic to insects, and the oily stuff also clings to their respiratory pores, suffocating them.
To kill carpenter bees and their eggs and young in the nest, just attach the straw to your can of WD-40, shove it into the nest as far as you can, and then spray until you see foam and liquid coming out. Take care to protect painted surfaces, and do this at night when all the bees are inside resting.
One good application should do it!
Carpenter Bee Traps Can Depopulate an Area Easily
If you know carpenter bees are active in the area but you don’t want to go through the trouble of trying to reach or track down their nests, you can protect your property by setting up carpenter bee traps.
These usually consist of a special wooden block with pre-drilled holes that will attract bees, but it drops them into a glass or plastic jar that they can’t get out of.
Eventually, the bees die. You can hang these up near areas of known carpenter bee activity or place them near vulnerable structures ahead of time to lure the bees who are attracted to the notion of an easy nest build.
How Can You Deter Carpenter Bees?
Like so many other things in life, things will go a lot easier for you if you’re able to prevent the problem from occurring in the first place. It’s no different for carpenter bees…
If you can stop the bees from nesting at all, or keep them from returning to previous nesting areas, you can prevent damage and save yourself some work. Do all of the following and you should notice a lot fewer bees next year.
Keep Wood Surfaces Painted or Finished
Carpenter bees, as a rule of thumb, only build in dead wood. More than this, they greatly prefer wood that is weathered and easy to chew.
Finishing your wood surfaces with paint, stain, lacquer, or any other coating will greatly deter carpenter bees because they won’t try to chew through such surfaces. Or at least, they are a lot less likely to try them.
Fill and Repair Cracks or Holes
If you’ve got cracks, knot holes, splitting, and other wood damage starting, you need to make it a point to address them one way or the other. Carpenter bees are attracted to these weak points because they are easy places to begin drilling their nests.
Use wood filler and sand flush or any other method of repair as appropriate to make it less attractive to carpenter bees overall.
Cover End Grain with Flashing or Other Hardware
You’ll probably find that exposed end grain on any kind of wood, especially on thick fence posts, is highly attractive to carpenter bees for all the reasons I’ve already listed above.
Basically, the easier the wood is to penetrate and chew, the more likely it is it will be targeted by bees. Carpenter bees are also attracted to where other bees are living successfully, meaning the damage can pile up quickly!
Your best bet for protecting end grain from the attention of these bees is to just cover it up using flashing, caps or any other kind of hardware that will completely enclose it.
End grain is difficult to finish and paint, and it degrades quickly when it is finished, so this approach can save you some aggravation.
Keep Garages and Outbuildings Closed
Carpenter bees are entirely happy to start building in quiet out-of-the-way places, and when they are moving into your neck of the woods early in the season, around mid-spring, will be giving any open sheds, carports and garages a lot of attention.
Keeping these areas securely closed up will take away some of the most attractive nesting opportunities for them and make it more likely that they will move on entirely.
Fill In Old Carpenter Bee Nests with Steel Wool
Carpenter bees will happily reuse vacant nests that are left behind from bees that came before them, and this means you have to be vigilant about filling up those old nest holes if you don’t want new tenants.
Use a caulk or wood filler to block up the hole after you’ve stuffed it with steel wool; this will prevent the bees from excavating it, and if by chance there are any bees still inside they won’t be able to get past the steel wool.
Keep Your Deck Sealed and Weatherproofed
Because decks get so much foot traffic they tend to break down quickly and this makes them a favorite target of carpenter bees.
Railings, posts and columns are where you will find carpenter bees furiously drilling away if you don’t keep your deck painted and sealed.
Use Decoys
One of the best things that you can do to keep your property from being torn up by carpenter bees is to give them an easier, better option. Plus, you won’t have to kill them if you go this route!
These ‘woodworker’ bees, like all bees, are critically important pollinators and their numbers struggle more and more every year. They need a little help too, you know!
Anyway, you can get or make what is called a bee house, which is basically an attractive, soft block of wood or a series of bundled, hollowed sticks that you can leave out for the carpenter bees to nest in.
Because their nests are so laborious and costly (in resource terms) to construct, they are always on the lookout for an easier option.
Provide that easier option and they will spare your stuff, and you can feel good about helping the bees.
Tom has lived and worked on farms and homesteads from the Carolinas to Kentucky and beyond. He is passionate about helping people prepare for tough times by embracing lifestyles of self-sufficiency.