If you have found wasps nesting in the wooden furniture in your yard, you might want to get rid of them. Here’s how to get rid of mason wasps and whether you need to do it at all!
Mason wasps are fascinating creatures that are known to build nests in tiny deep holes in wood and concrete using mud to create chambers.
These white and black wasps are extremely useful in controlling pests in your gardens and are considered good pollinators.
But unfortunately, people think that these wasps are responsible for destroying wooden furniture by carving holes to build a nest.
What if we tell you that it is totally wrong? Yes, mason wasps do not carve holes in furniture. This article will help you understand these wasps better:
Do Mason Wasps Eat Wood?
Sometimes you will come across several holes in your outdoor wooden furniture; these holes are the ideal spots for mason wasps to build their nest.
But you should know that these wasps don’t create these holes. Instead, they tend to occupy the pre-existing holes made carved by yellow jacket wasps, wood-boring beetles, etc.
This wasp species don’t chew wood to make paper nests. Instead, they are known to use mud to build their nest cells.
Mason wasps usually prefer to nest in holes that are about 1/8 inch in diameter. The holes are actually smaller than the wasp itself, and most of the time, they have to back out like a car reversing out of a parking spot.
The female wasps like to go deep into abandoned beetle holes to lay eggs. They hunt caterpillars or other insects to feed the larvae.
Do They Sting?
Mason wasps are capable of stinging but are usually less aggressive toward humans. These wasps are docile compared to other wasps, like a yellow jacket.
A mason wasp will only sting a human if they are provoked by one.
You should remember that a mason wasp is capable of delivering painful stings. Therefore you should be extremely cautious around them.
Are They Social? Do They Live in Colonies?
They are solitary wasps and use pre-existing wooden holes made by beetles and other wasps to make unique nests using mud. These nests look like pots in shape.
The females nest alone in deep old beetle holes where they construct a network of chambers with mud.
They lay the eggs in these chambers and later fill them with prey like leaf beetle larvae and caterpillars.
Once she has filled enough sections with eggs and food, she will cap off the nest’s entrance with mud.
Can They Get in Your House?
Mason wasps will not build a nest inside your house. They prefer to build nests outside, preferably in spaces like your garden or yards.
Also, since they don’t live in colonies, the nests are relatively small compared to other social wasps like the yellow jacket. Therefore it can be hard to track down these nests.
If you are looking to track a mason wasp nest, search in higher corners or edges of your house.
Are They Beneficial?
Adult mason wasps primarily depend on hunting and consuming other insects like caterpillars, cutworms, and more.
They are also known to feed on nectar. This indicates that mason wasps are good pest controllers and decent pollinators. Having them in your yard will keep unwanted pests away.
Can They Be Dangerous?
Though the chances of a mason wasp attacking a human are less, but you approach them with caution as they will sting if they feel highly threatened. The sting delivers a great of pain and causes swelling.
However, if large numbers of mason wasps build nests in the brick walls of your house, it could weaken the structural support of the building.
The nest-building process compromises the mortar in between the bricks. The nest-building process in wooden furniture also weakens the strength of the furniture.
How To Remove Them?
Since these wasps are beneficial insects, there is no need to remove them.
But if there are too many mason wasps flying around your house, you can drive them away by removing any wooden furniture in your yards.
If they are any wooden outdoor furniture, clean them and try to seal all existing holes using polyurethane or wood putty.
Wasp sprays can be used to kill these wasps, but since they are harmless, there is no need to use pesticides to kill them.
Simply seal the nests with wood putty to get rid of these wasps. If you face difficulties in spotting their nest, you can call pest management professionals to help you out.
Frequently Asked Questions
How do you keep wasps away permanently?
You can keep wasps away permanently by getting rid of pests in your yards and gardens. This will shorten their food supply.
You can also plant wasps-repellent plants like mint, pennyroyal, marigold, and wormwood to keep them away from your garden.
Where do mason wasps nest?
Mason wasps build active nests in pre-existing wooden holes carved by other insects like yellow jacket wasps, wood-boring beetles, etc.
These wasps are solitary in nature and often build small nests using mud to create and line the different chambers in their nest.
How do you get rid of a four-toothed mason wasp?
You can use wall putty to cover the wooden holes that these black wasps use to build their nest.
You can also use polyurethane to cover these holes. The use of wasp spray will directly kill these wasps, which is unnecessary as they are harmless until highly provoked.
Are mason bees aggressive?
Masonry bees are non-aggressive compared to the other bee species.
They rarely sting and are known to lay their eggs inside existing tunnels or holes made by wood-boring beetles or yellow jacket wasps.
These bees won’t sting until and unless a human tries to manhandle them.
Wrap Up
Mason wasps are beneficial insects and great pest controllers and pollinators.
Many people have the misunderstanding that they carve holes in wooden furniture, but they simply occupy the pre-existing holes and are known not to consume wood.
We hope this article clears all your doubts regarding this fascinating insect. Thank you for taking the time to read this piece.
Reader Emails
Mason wasps can spell trouble in a lot of ways – their stingers are a concern, but many people are also worried about their wood-boring habits.
Please go through some of the letters we have received over the years checking in with us on how to get rid of them.
Letter 1 – Mason Wasp
Boring Wasp?
Hello, I live in south west ohio and about the begining of spring noticed a couple holes bored uundeneth the railing on my deck. I just finally seen this wasp going in and out today. It is black with white markings, and I did’nt know wasp would bore into wood to make nest. I would apreciate it if you could identify it for me, I’ve looked all over the internet, but can’t find it any where. Thanks.
Brian and Kim
Hi Brian and Kim,
We wrote to Eric Eaton for advice on your wasp. Here is his answer: “The wasp is a mason wasp, Monobia quadridens, probably the largest species of Vespidae: Eumeninae in North America. Females paralyze caterpillars as food for their offspring. They nest in the abandoned tunnels bored by carpenter bees, or in similar cavities, partitioning the space into several cells, stacked one in front of the other. These are peaceful, solitary insects that need not be eradicated.” So the wasps didn’t make the holes, they just moved into a vacant unit.
Letter 2 – Four Toothed Mason Wasp
Subject: black wasp with white bands
Location: Fairfax, VA
July 27, 2014 12:27 pm
I photographed this attractive wasp (at the same time as a Great Golden Digger Wasp) on 7/27/14 in Fairfax, Virginia. I haven’t been able to find a reference to ID it. Can you help?
Signature: Seth
Dear Seth,
Your images of the Four Toothed Mason Wasp, Monobia quadridens, are positively gorgeous. According to BugGuide: “Usually nests in wood borings, but sometimes burrows in dirt banks. Sometimes takes over abandoned nests of carpenter bees or ground bees, also Sceliphron (mud dauber) cells. Nest is provisioned with caterpillars, and cells of nest are separated by mud partitions.”
Letter 3 – Mason Wasp from South Africa
Subject: Whats this bug?
Location: 26.036731ºS, 27.698263ºE
January 12, 2016 3:13 am
I’m from South Africa and often see this wasp-like bug this time of year, mostly in the shady part of the garden.
I can, however, not seem to find out what it is and would appreciate you assistance.
Thank you
Signature: Garfield Krige
Dear Garfield,
This identification proved a bit challenging for us, but we believe we have correctly identified your wasp as Synagris mirabilis on iSpot. It is called a Paper Wasp on Nature’s World of Wonder, but North American Paper Wasps are in the subfamily Polistinae, and your individual is in the subfamily Eumeninae, the Potter and Mason Wasps, so we are referring to your individual by the common name Mason Wasp.
Dear DAniel,
MANY thanks for your quick response – we really appreciate it. And what an interesting insect it turned out to be! I (I am Garfield’s wife) do a monthly info letter as we live in the Cradle of Humankind – which is a UNESCO world heritage site, and I try and get people more interested and aware of conservation, plants, insects and animals on our Estate and in the area.
Insects fascinate me, so in one of my letters I have written on the Rhino bug and once on the praying mantis etc. etc. I can’t ever write too much as not everyone wants to read long letters (people are lazy!) and so I try to keep it short-ish!
When we moved out here (it is outside of town) we noticed how many interesting species of plants (some rare) and other forms of life we have and so I decided in stead of looking things up and keep some sort of record just for us, I wanted to share with the people on our Estate as well. So I first started the monthly letter and a couple of months later the website. The website (juuuust in case you feel like having a sneak peek!) is www.sterkfonteincountryestates.org.za and all the letters are under Downloads. It is a big job, I have to read up a lot (I am no scientist) and double check things and so on.
Anyway, enough of me, thanks for a great and interesting website, you really helped us out and now I can write in the Feb issue of my letter about this wasp!
Kind regards,
Elmarie Krige
Thanks for the response and link Elmarie. I did a quick peek at your site and I checked out the Invasive Plant Species page. I am about to head to our local Moon Canyon Park to remove invasive Castor Beans. Invasive species are a tremendous problem in open spaces that are designed to preserve local flora and fauna.
Daniel,
Over here we have the DREADED Pop Pom weed which is a HUUUUGE problem in South Africa. It takes over valuable land and is extremely difficult to get rid of. Not much done from givernment side…things are sliding, what can one say. Anyway be sure to have a free stay with us should you ever wish to visit South Africa! We could show you lots of interesting things in just area alone.
Kind regards,
Letter 4 – Mason Wasps
Subject: Wood boring….wasp?
Location: 48108 Ann Arbor, MI
June 3, 2016 10:05 pm
Hello! These guys are making a condominium in my barn. What are they? I am in zone 6b SE Michigan.
Signature: Mary
Dear Mary,
We embarked on a relatively lengthy internet search in an attempt to identify your Mason Wasp in the Subfamily Eumeninae, beginning with unsuccessfully scanning through all the genera on BugGuide. According to BugGuide: “Most species nest in pre-existing cavities (e.g., old borings in wood, hollow stems, crevices in rocks). They are called mason wasps because they use mud (or less commonly sand) as partitions between their brood cells. Some species construct nests in the ground.” We then found this great site, Bug of the Week run by Michael J Raupp, Ph.D. that has a wonderful posting of Mason Wasps using pre-existing cavities. At last we found a very similar looking individual identified as being in the genus Symmorphus on Bug Eric, the awesome site run by Eric Eaton. An image on BugGuide of Symmorphus canadensis looks very close to your species, but there is no indication that the females will excavate a nest if they cannot locate a pre-existing cavity. We will contact Eric Eaton to get his opinion. We suppose these beams may have been infested with some other boring insect and the holes were quickly appropriated by the Mason Wasps.
Oh thank you!
There’s a lot of them. They go into the holes, also.
Super happy to see these guys on your site. I have been seeing them out along my front porch where we have, or rather had, oooooodles of carpenter bees that I very much adore. I thought at first they were bald faced hornets which was very scary, but your site helped me identify them more accurately and I’m much less nervous to see four or five of them hovering around the railing and going into the little bore holes. Thanks for all the great work you guys do!
Saw one of these on my front porch in Topeka Kansas on July 4th 2016
Just found one of these in my garage here in SW Michigan and scared me half to death!…..lol. Are there some pros and cons to these guys or any other concerns ?
First time I have seen these in southern Vermont. Over the past couple of years we have had Carpenter Bees destroying the wood on the garage, now these Wasps have shown up to lay eggs in the holes.
Just saw one of these in my house in Cicero, NY. Scared the hell out of me, I have never seen one of these before.
Just saw one of these for the first time on my back patio going for flower to flower in Overland Park, KS.
A squadron of them have taken over my kitchen pouch from the carpenter bees. First time I’ve seen them on long island. Thay do get in your face.
One on Choctawhatchee River in Ebro, FL.
I have one on my deck. Seems to like my sedum plant. Do they sting?
Freeburg, IL
Just photographed one just south of Ft. Worth, Tx.
It was not aggressive as I snapped a close up with my phone. Thought it was a mud dauber, as they have all begun to fly in the last two weeks!!!
We have tons of these we are in Martinsburg, WV
This is neat guys. This thread has tracked them for 7 years now. I have a few of these hiding in the deck holes but with the wood shavings around I have to say I think they burrow in it as well. Seem to check me over when Im on the deck but never overly aggressively. All that said, they are now in Ontario Canada. June2021
Just saw one. It was here last year too. Cambridge, Ontario, Canada. It is investigating the carpenter bee nests.
Last year, a big black wasp (I think it was a four toothed mason wasp) flew in carrying a huge larvae and placed it in the carpenter bee nest.
Just ID’d one in my backyard in the middle of D/FW area. Obviously looking for holes…hopefully not finding any. We don’t need any more stinging flyers!
A number of this wasp species appeared in Northeast Texas. First time seeing them in the 30+ years living here. Oddly, they congregate everday under my cattle trailer. I cannot find their nest.
I seem to have them now just over the past couple of weeks in SC. Regular wasp were abundant thru the summer. Now fall and I have these guys! And they do come right by ya but haven’t been aggressive (yet?)