Call an Exterminator to Get Rid of Yellowjackets Nesting in Walls
By Chris Williams on August 3, 2015.
My wife saw some wasps going into an opening in the bricks on our house. I sprayed some wasp spray into the hole but it didn’t seem to do much good. The wasps are still entering and I don’t know what else I can do about it. Any ideas?H. P., Millville, MA
My first idea (and you knew this was coming) is that you should contact a professional exterminator who has the equipment, knowledge, and pesticides to get the job done. Not to mention that if anyone gets stung, it will be him!
Your wasps are probably yellowjackets. It’s not unusual for yellowjackets to nest in homes instead of in the ground. They build their papery comb nest, usually in a wall void, and come and go through an outside opening (see When Yellowjackets Nest Inside Homes!). Often, unless they accidentally emerge inside the house somewhere, the residents don’t even know that they are living with a yellowjacket nest.
It’s Not Easy to Find or Treat a Void Nest
The main problem with trying to treat a void nest is that the nest is not necessarily right behind the hole where the wasps enter. It can be several feet away in any direction. Your spray, no doubt, didn’t make it to the nest. That’s why it’s important to inject an insecticide dust or a fogging spray that can fill the entire void space. You can sometimes locate the nest by listening for buzzing sounds behind walls (a stethoscope helps). In some cases, an injection hole may have to be drilled to reach the nest.
You tried. Now it’s time to give the specialists at Colonial Pest a call. We have many years of experience in treating yellowjacket and other wasp nests.
Do You Need to Remove the Nest Itself?
After the yellowjackets are killed, you’ll need to decide whether or not to remove the nest. This decision should be based on where the nest is located (if you even know), how expensive and difficult it would be to remove it, the size of the nest, the time of year, and probably other factors that you will think of. The nest is not reused next year, but larvae left in the nest could attract other insects. There could also be an odor problem if the nest was packed with larvae that are now dead and rotting. See Should a Wall Void Yellowjacket Nest Be Removed?