Yes. As seen in the wasp video below, the Cypermethrin will kill them off quickly and effectively. It's easy to use with any good pump sprayer and will stop them from coming back and starting new nests. Next fall, it would be smart to do a thorough dusting with the Drione if you want to stop them from using your house for hibernation which they most definitely must be doing.

Any ideas about how to identify where they are coming from or to find a nest?

Thanks. You have a great website.

There are many species of black wasps which "over winter" or hibernate. Log cabins are classic structures where they like to spend their winters. The logs tend to attract many types of insects including bees and wasps. In the fall they find small cracks and crevices in which to hide and live throughout the cold winter. Come spring, they'll emerge back to the wild but during the winter months, some will find their way into the living spaces.

Unfortunately, there isn't really any main location where they are coming from. During the winter, they don't form a nest. They simply find cracks and hide when it's cold. Unfortunately, some of these cracks will lead to the living area so some of the wasps that are on your cabin will find their way inside seeking relief from the cold of the winter. That being said, there are two things you can do which will stop this from happening.

First, you should get some Drione and do a thorough dusting this spring. The drione will kill off any that are hiding in the cracks. A few weeks later you should do a good spraying with the Cypermethrin mentioned in our wasp control article. This will help keep any from forming nests this spring and summer. Next fall, you should again dust and spray with the Cypermethrin to stop any from hibernating on the cabin. This approach will keep your living area wasp free during the winter.