Spring has sprung! Ornamental trees are blooming, flowers are growing and insects are awakening. This is an exciting time of year. Mother nature gets to show us that she is omnipotent – nothing can stop her. And one of her creatures which is active now is the carpenter bee. Carpenter bees are prevalent throughout the United States. Although there are different species, the most common is big and resembles a bumble bee. You may find it foraging around flowers, shrubs and under the eaves of buildings. This bee is unique from most because it will bore into wood to make its home. They are a nuisance and can cause damage to any wood on your property. They also bother homeowners by “attacking” them though they rarely sting. To keep your building free of carpenter bees, you must know their biology and habits.



Carpenter bees bore holes into wood overhangs, fence posts, and trees. They will crawl between cracks of siding and roofing. When they bore in wood, the hole they drill is about 1/2″ wide. This hole will go straight an inch or two and then turn 90 degrees. The following video shows close up a freshly drilled hole with a female carpenter bee just inside.


This new portion of the nest becomes an egg chamber. Eggs are laid at the end of these chambers and many times in “sub” chambers which stem off the main chamber. Food is placed alongside the egg and then capped and sealed tight. It is common for an egg chamber to be two or more feet long with 10 or more sub chambers. Here is what a typical carpenter bee hole will look like when seen on a 2×4 piece of pine.


Carpenter Bee Hole

If you could “peer” inside a hole, the typical chamber would look like this.

Carpenter Bee Nest Chamber


Typically the female carpenter bee will stand guard at the nest entry hole. She will defend the nest aggressively and she is armed with a stinger. Once the drilling has been completed, she will spend her days foraging for food. You may find her working Azaleas, Bradford Pears, Daffodils, Pansies and any plant which will provide pollen in early spring.


Male bees will be hanging around these same plants hoping to find a receptive female who is still interested in finding a mate. The male bees are naturally curious and will buzz around anything moving including people, pets just about anything they see moving. This buzzing scares people into thinking they are being “attacked”. In fact, the male bee does not have a stinger! He has a distinctive yellow face, which may be seen while he is in flight.


Female bees have no interest other than collecting food. As stated above, they have a stinger but their face is black which is in contrast to the male bees. Carpenter bees are commonly mistaken for bumble bees. There are two main differences.

1) Carpenter bees are generally larger.

2) Carpenter bees have an abdomen which is shiny, metallic and black in color. Their abdomen has no body hair. Bumblebees have yellow and black body hair on all body parts. The following video shows a female carpenter bee closeup as she is chewing an entrance hole to a newly formed nest. Note her shiny metallic abdomen.


In addition to “attacking” residents, carpenter bees are a problem because they tend to return to the same wood or location where they were born. Old nests are used year after year. If the original nest is occupied, other female bees will drill new nests. A single nest one year will become two or three the next. Problems rapidly escalate and soon you may have hundreds of holes.


When you have numerous carpenter bee nests, you will have numerous larva. The larva of carpenter bees is large and noisy. They make enough noise to attract woodpeckers. Buildings which have woodpeckers damaging exposed wood probably has some type of larval activity which is attracting the birds. This insect is most likely carpenter bee larva.


Hornet KillerPT-515To get rid of carpenter bees, you must think long term. The nuisance male bees are easy to kill with PT-515 WASP FREEZE. Try to get as close to them as possible and then spray directly at them making sure to keep the spray on them as long as it takes to kill them. This is usually 3-5 seconds. If you have a lot of females which are boring or hanging around looking for a place to bore, they can be a little tougher to kill. Use the BEE AND HORNET KILLER which seems to work a little faster with less waste.


Hornet KillerBee Hornet Freeze:


Unfortunately, killing the male bee will do nothing to stop the cycle. You must treat the nest with some material which will last a long period of time so it will effectively stop the larva. If you spray liquid residuals in their hole, you may kill the female. The eggs are protected, however, and six to twelve months later the larva will emerge. Since liquids are absorbed by porous wood, the treatment will be gone when the larva finally hatches. This means the larva have a strong chance of survival.


CorksDrione DustTo insure complete control, use a dust called DRIONE. It has a desiccant (dehydrating) action and when the larva emerge they will be killed quickly. It is recommended that entry holes are treated with Drione and then sealed using a special 1/2″ CORK. This will protect the dust from breaking down and enable it to last long enough to kill any emerging larva in the future.

Drione DustDrione:



Plugging the holes with a cork instead of using wood filler means the tunnels will be accessible for emerging bees when they hatch from their protective egg chambers. When they do finally emerge (which will be either later this year or early next year), the bees will crawl over the Drione and meet their demise. Too many times we get calls from customers who have used silicone sealant to “fill” the holes instead of just capping it with a cork.

The problem with filling the tunnels with a sealant is that emerging young will not be able to move over the Drione. In fact they’ll be forced to drill new exit holes which will be chemical free. Many times these nests will lead into the home or some other location that’s hard to see or treat. To avoid this complication, do not seal the holes. Instead, cap them with corks and allow the tunnels to stay open and useable by bees that are not yet fully developed or active.

Lastly, the other benefit of using corks is that they will enable you to tell which holes have been treated and which (if any) are new.


CrusaderSince the holes can penetrate several feet, you will need to use an applicator like a HAND DUSTER. This tool will help you to apply the dust with enough force to reach deep in the nest where the eggs and larva will be living. Here is a video showing just how to treat their nests using a hand duster.

CrusaderHand Duster:


Long Reach Dust-RDusterIf you have a lot of holes to treat, you should consider the DUST-R. This device holds almost a whole pound of Drione and because of it’s unique pump handle design, requires very little effort to treat a hole. For large jobs, it’s a real help. Nests can be treated in a couple of seconds. If the holes are just out of reach, use the LONG REACH DUST-R which is essentially the same device except it has a series of extensions that lengthen the unit to over 7 feet long. This means the average person standing on the ground can treat nests over 12 feet high without the use of a ladder!


Long Reach Dust-RLong Reach Dust-R:


DustickFor really high nests, the DUSTICK or the DUSTICK DELUXE KIT might be the tool for the job. This duster is over 20 feet long and can be used to access nests which are over 25 feet up with little effort! It’s also a great tool for infestations where carpenter bees are foraging under facia boards or siding which take forever to treat using a ladder. This video shows the Dustick being used.



To get rid of carpenter bees that are foraging to start new nests, you must first finish all exposed wood with a protective paint. A hard finish may deter carpenter bees. However, the author has had his own home attacked and the bees didn’t seem to notice the freshly painted surfaces. The Latex paint which was just applied didn’t seem to slow them down at all. Furthermore, the author has seen them bore through varnish, stain and just about any type of finish. Since cellulose is where they want to call home, wood used on any structure may become a target. If the structure is a log cabin or one with natural wood siding with shakes that are exposed, expect to be attracting carpenter bees every season. All wood gives off a decay odor which attracts these bees and once the structure is found the bees will start their nest making.


CypermethrinTo stop them from boring new nests, spray CYPERMETHRIN. This product is active against many pests including carpenter bees. Mix it at the rate of 1 ounce per gallon and spray it on any wood surface where carpenter bees may want to bore into wood trying to create a nest. One gallon can treat 500-1000 sq/ft. This application rate works well when treating cedar homes and log cabins. These structures are particularly subject to carpenter bees. If you want to keep them natural it means you will have to do more spraying to keep away carpenter bees and other wood destroying pests.



Pump SprayerApply the Cypermethrin once every 2-4 weeks in the spring when carpenter bees are most active. Once a month applications throughout the summer will probably provide protection but you may need to increase the applications to every 2-4 weeks in the fall as well to get a complete season of carpenter bee control. Although rain and humidity will break down the chemical, it is active enough so that even trace amounts will chase these bees away and force them to find and build nests elsewhere.  Most any SPRAYER will do the job and we’ve got a few that can reach up 20 feet or more making the treatment more effective. This video shows that a “pinstream” spray is best suited for reaching those overhangs and other high places where carpenter bees will many times want to nest.

Pump SprayerPump Sprayer:

Now that you have the chemical and sprayer, be sure to get good coverage when treating by spraying high and wide. Remember that spot applications are not suggested. In other words, if you have activity in one section of an overhang, be sure to treat all of it since the carpenter bees will probably just move to the untreated section. Since they can sense the Cypermethrin, they tend to avoid where it was sprayed and move to areas which are not protected. Generally, after they find it at several places on your home, they will leave altogether. Remember also that old holes release odors and smells that tend to attract new carpenter bees looking for a good nest sight so be sure to treat as many as possible with Drione and seal them up. This will insure they don’t become a “recycled” nest. If they are too high to access, be sure to spray them with the Cypermethrin which should offer some protection. This will make the carpenter bees avoid the area and help to mask the hole’s odor so it won’t be able to attract as many.


NBSFor longer lasting bee repellency, be sure to add some NBS REPELLENT to your paint/stain the next time you finish your home. Just adding it the paint you plan on using to repair and seal the nests you treat can help as well. NBS is an organic insect repellent. Formulated to be used by adding it to any paint or stain, you don’t have to do anything odd or unusual to apply it. And treatments will last 1-2 years adding long term repellency to the exterior coating.

NBSNBS Repellent:


Made from plant oils, this 100% natural product isn’t a pesticide and it won’t kill any insect so you still need to dust with Drione to control existing populations. But bees don’t like the NBS (neither do wasps and other invasive insects) and they’ll avoid siding, fencing, railing, decks, logs, overhangs, soffits and pretty much any place NBS is applied.


NBSNBS can also be mixed with nothing but water and applied with a pump sprayer to your siding, outside furniture, trees, shrubs and any area in the yard where you’ve got some unwanted insect activity. When used in water, the residual will be a lot less compared to when it’s mixed with paint or stain so you’ll need to apply throughout the season every 1-2 months. And remember, it’s a not a pesticide so don’t expect to see anything die. For that, use the Cypermethrin.

NBSNBS Repellent:


CARPENTER BEE KITSWe have put together several carpenter bee “kits” that essentially combine several of the products listed above into one “sku”. These will help by combining the needed dust, equipment and spray to treat anything from a small problem right on up to the major infestation. There are basically 4 kit types with Kit 1 good for 5-10 nests, Kit 2 good for up to 25 nests and Kit 3 good for 50-100 nests. See which kit is best for you by reviewing the included components on our kit page here:


Come spring, insects will rebound from a long and cold winter. The carpenter bee is just one of these insects. Treat their nests directly with Drione to insure long term control. Use Cypermethrin on decks, overhangs and fence posts to stop further nests from being drilled. Carpenter bee awareness and control will help eliminate these “attacking” bees from harassing you, your family and your home.


Give us a call if you need further help. Our toll free is 1-800-877-7290 and we’re open Monday through Thursday, 8:00 AM to 7:00 PM. On Friday, 8:30 AM to 5:00 PM and on Saturday, 9:00 AM to 2:00 PM (Eastern Standard Time).

Email questions here:

Order online and get a 5% discount! We ship fast with 99.9% of all orders shipping within 1 business day!!

Learn more about BUGSPRAY.COM and why it’s never been easier or safer to do your own pest control.

Please show your support for our business by purchasing the items we recommend from the links provided. Remember, this is the only way we can stay around to answer your questions and keep this valuable web site up and running. Thanks for your business!


Here are direct links to all the products listed in our article:

Wasp Freeze:

Hornet Killer:



Hand Duster:

Dust R:

Long Reach Dust R:


Dustick Deluxe:



Insect Repellent:


March 5, 2015

Comments on CARPENTER BEE CONTROL Leave a Comment

March 18, 2012

Bill Snapp @ 11:02 pm #

What kind of paint or sealer can I use to prevent them from boring holes?

March 19, 2012
March 23, 2012

Katherine Beeson @ 9:52 am #

Thank you for this page. I have had Carpenter Bees for many years in my house roof…….I was told to spray the wood with wasp spray. When the Bee eats into the wood it wood make it so nasty that they would leave. I like what you say about the bees and how to get rid of them…I’m 60 years old and my husband died last year and now I have to try and kill these things by myself. I will be buying all I need from you soon. Thank you so much for the advice…the duster may just be the ticket for me.

Once again, thank you.

March 29, 2012

John Bullock @ 11:39 am #

I bought some Drione about 10 years ago to treat carpenter bees in my previous house. It seemed to work well. We now have a carpenter bee problem in a large wooden arbor at our current house. I have some of the Drione left. Is it still good enough to use or does it lose it’s effectiveness over time? (It’s been kept in it’s original container with the cap screwed on.) Thanks!

April 2, 2012

Sallie Carlino @ 1:03 pm #

The carpenter bees I want to eliminate are mostly inside a large fenced area where all my dogs roam. Is the treatment harmful to pets?

April 3, 2012

Richard Cozby @ 3:29 pm #

I noticed that you or someone was using cork to plug the holes. Can you use caulking to fill in the holes ?

April 6, 2012

J P @ 2:18 pm #

My home is 90% brick but is an older home with trim and eves of cedar. After treating and plugging all the holes the carpenter bees have made, would aluminum or vinyl siding be an option to install over the cedar? And would this help eliminate the bee problem all together?

May 1, 2012

Mary Coble @ 5:50 pm #

My husband was under the impression that carpenter bees would not bother with pressure treated wood. Is this not correct?

July 10, 2012

Rosemary @ 6:44 am #

@admin: Is it true that brown paint will attract carpenter bees? Thank you.

June 22, 2012

Fillmore Corpus @ 1:37 pm #

I dusted for carpenter bees with drione dust (great stuff, and the dust stick also works great), and within 2 – 5 minutes 2 to 3 bees fell out and died. I then plugged the hole with a cork. Now the next day I see another carpenter bee flying around the holes I plugged. Should I then as a follow up spray with cypermethrin? I am assuming that this bee will not just give up and go somewhere else.

Also, thank you for your very informative videos, help when I called, and your thorough knowledge about carpenter bees. Thanks.

July 28, 2012

Arlene Agler @ 8:40 am #

Hello – we think we have carpenter bees in our maple tree. Every morning they are flying around the tree. If we spray them directly will it kill them and what kind of product can we use? They are not out in the afternoon and evening. Thank you.

September 2, 2012

Marlene @ 10:20 am #

Hi, we have had a noise in our attic and thought it was mice but have not caught any. The noise was becoming louder and louder and in the same place above our bedroom. When I tapped the ceiling in our bedroom, it was very soft like I could probably put a stick through it and I heard a buzz and then silence. My husband went in the attic and removed some insulation and some bees started coming out. We have siding on the entire house and just had a new roof installed 1 1/2 ago. How could they have gotten in our attic and what can we do to get rid of them? I don’t want them to go through the ceiling in my bedroom!

September 4, 2012

Rick Wood @ 9:45 pm #

Thank you for your informative web site and videos. After having read and watched it I definitely want to buy the drione and cypermethrin from you. My situation is that I have carpenter bees in an old stump in my back yard – right next to where I decided to build a grape arbor. I have this instinct to get a stump grinder and obliterate it. I suppose I’d minimize the opposition by treating with the drione first, grind out the stump and then spray the remaining area with cypermethrin.
Any thoughts?
Best regards,
Rick W.

September 5, 2012
May 8, 2013

Tom @ 6:13 pm #

These are but one of the buzzing, flying, stinging insects “plaguing” us. It is unpleasant to be out in our yard to work, play or chill. They often pick places around our only entrance, exists and seating area. The carpenter bees (shiny bodies and all) have bored not only into wood settings but under our cement stoop and in the ground.

None of your article deals with those not building in wood but I assure, these have the shiny bodies and all. Also, they sometimes appear in my bathtub already dead (very odd!). Is there anything different I need to do to safely get rid of this problem — now and “for good”? My biggest concern right now — pertaining to these type specifically — are the ones in the ground that I fear have a big nest that has weekend the ground. Concerned someone — likely postman, landscaper or someone mowing — will put their foot and leg through the ground and right into their nest.

May 29, 2013

Chuck Alcini @ 2:15 pm #

Our home has an exterior of brick and cedar. Every year we have a problem with the carpenter bees boring into the cedar siding and insecticides are only a temporary solution. We are considering having the cedar treated with RhinoShield, but I would like your professional opinion regarding this before we make a decision.

Thank you,

Chuck A.
Dryden, MI

June 1, 2013
June 11, 2013

Marcie @ 11:33 pm #

Thank you for the informative website. We have a carpenter bee problem in our daughter’s wood swing set. We definitely want to get rid of this pest but are concerned about the toxicity of pesticides. What treatment and products would you recommend that are safe for use around a play structure and kids?

June 12, 2013
June 14, 2013

Ben @ 6:55 pm #

This may sound strange but I have a rock retaining wall and I have carpenter bees living in it. I’m pretty sure that’s what they are. They are big fat bees that make a loud buzzing noise and have black rear ends but are yellow with a black spot on their backs. I sprayed in there once but 2 days later I saw them again. So I sprayed the inside with with an expanding foam to try and seal it up. I can’t “cork” holes in a stone fence and there are too many potential entrances between the rocks to do so anyway. It has now been 6 days and everyday I still see bees trying to find a way in. They’re not too happy but boy are they persistent. Any advice? I want to grout all the holes but this may not be easy with bees buzzing around me.

Ben @ 7:04 pm #

Okay, I see that you said above that carpenter bees can burrow into ground nests and get into root systems…. This makes sense because I had a birch tree die in the ground area behind the retaining wall a year ago. It was removed but the roots are still in there (Birch borers killed the tree). So now there is dead decaying roots in the ground there for sure. I have a new fringe tree (small) growing nearby there too. So first, I’m worried the insecticide will get into the ground and kill my new tree. Secondly, I have to get this under control and then seal every crack in the rock retaining wall. So I still need advice but just wanted to add that. Thanks.

August 18, 2013

Mary @ 10:24 pm #

We have an all brick home except the cedar front porch. Last year we noticed what we thought was honey bees at the end of the porch away from the door. Spraying wasp spray into the crack they were gong in and out of seemed to get rid of them. Within the last two weeks we have so many bees at the other end of the porch, that we cannot use the door anymore. These bees do not look like the pictures of carpenter bees, nor can we find a hole that they created. These bees seem to be smaller and don’t appear shiny. They do however go in and out of cracks were beams connect. We have sprayed and caulked to close where they were going in and out of (didn’t read your advice prior to doing that). Can this be another type of bee and should we still use the Dione?

August 19, 2013
August 20, 2013

Gary @ 12:31 pm #

I have had an infestation of carpenter bees all summer in a vinyl drainage pipe coming out of a rock wall planter between my drive way and front door. After reading your very helpful site, I now know that the spray and foam that I used will not work permanently. I am guessing that Drione will exterminate the live bees and remain for the larvae, but how can I seal the 4″ diameter end of the drain pipe? Thank you for a very informative website.

August 24, 2013

Anna Donaldson @ 2:23 pm #

We have a large wooden cabinet, probably 8 feet long and 2 feet deep. It sits in our carport. We are moving this week and I’d like it move it inside our new house. It has numerous carpenter bee holes. Am I basically inviting a carpenter bee infestation inside our new house? Since it is late August, can we assume there are still eggs or larvae inside the holes or have they already hatched? My husband wants to bring it in and just kill the bees if they emerge. What do you think of that? Thank you for your help!

November 16, 2014

Barbara Doiron @ 2:04 am #

I found a black and yellow bee on the floor of my utility room and it was sluggish. I killed it and threw it. My son had been doing work on our house and left a part at the top of the wall near the roof open. This is on the opposite end of my house from the utility room. We have had trouble with carpenter bees drilling holes under the roof of our deck, and my husband had been caulking the holes. In the utility room there is an AC vent that doesn’t have a vent cover on it. Could I have a nest in my attic? The thing is I’m not sure what kind of bee it was. I thought maybe it came in on someones clothes. Would spraying the opening near the roof and then closing it after a couple of days work? I’ve read about the chemicals you recommend using but if I don’t know what type of bee will it matter?

June 24, 2016

Bob @ 7:58 pm #

Hello there. Thank you for all of the information you provide for pest control. I have a carpenter bee problem. I just have a couple of questions. You say to plug the holes after a couple of days (after DRIONE treatment) and that it would be wise to cover the corks with cypermethrin. Should I spray cypermethrin immediately after I use DRIONE? And then perhaps spray the corks separately so they’ll be soaked when I use them? Or wait to use cypermethrin after I plug the holes so they’ll be sprayed as well? Thank you for your time.

July 20, 2016

Leave a Comment

Fields marked by an asterisk (*) are required.

Time limit is exhausted. Please reload the CAPTCHA.

Subscribe without commenting