As summer draws to an end we always know that we will see a marked increase in the presence of yellowjackets and hornets. Hornets, bald-faced hornets, are not common in our area. These are the ones that make the well known football shaped nests in trees. Yellowjackets, however, are very common. These are the little rascals that show up around our food and drink at outdoor events from now until freezing weather. They sort of look like a streamlined, turbo-charged, honeybee. While they are bothering our picnics, trying to gather food, they tend to be fairly tolerant. But start to disturb the area around their nest, normally in the ground, and their true aggressive nature is seen in full display!
Yellowjackets overwinter as a newly emerged queen from the previous fall. As the weather warms in the spring these new queens disperse and start looking for a nest site. This nest is often in an old rodent tunnel in the ground, but can also be in voids around old tree trunks or similar areas. The new queen starts building the nest, laying eggs, gathering food for the young, etc. She is doing all of this by herself. As the first new workers start to emerge they are tasked with making the nest larger, gathering food, raising the young. While these early nest stages are going on, through the earlier parts of the summer, the yellowjacket colony is very tolerant of disturbances or activities around the nest. But once we reach later summer, the colony has grown large enough that there are now guard bees whose only responsibility is to protect the nest. This is when unfortunate interactions with humans start to occur!
Unlike honeybees, that can only sting once, yellowjackets can sting multiple times, and I can tell you by experience that it hurts far worse than any honeybee sting! Once you encounter a yellowjacket nest the first thing you need to do is vacate the area. They will sting anything moving about in the area. Once they have calmed down a little bit, start watching them from a safe distance and try to determine where the nest entrance is. Yellowjackets will fly around very close to the ground and then enter the nest. Someway try to mark and note where this entrance is. You may want to come back in the late evening with a flashlight to carefully try to get the exact location of the entrance.
It is important, very important, to note that if you are allergic to bee stings DO NOT try these next steps! Hire someone to do it! Unfortunately there are no “natural” controls that are quick or effective. You will want to buy some of the foaming wasp and hornet aerosols that shoot a concentrated stream ten feet or more. Wait until well after dark when most if not all of the yellowjackets will be back in the nest. It is sometimes easier to have one person hold the flashlight on the nest entrance while the second person approaches the nest entrance. Fill the nest entrance with as much of the foaming spray as you can. These sprays have very fast knockdown and the foaming nature of them means that any yellowjacket trying to leave the nest gets covered with the spray. It will likely only take ten to fifteen seconds to complete this process at which time turn off the flashlight and leave the area!
The next day cautiously spend some time observing the nest entrance for ten to fifteen minutes to watch for any worker yellowjackets entering the nest site. If you see any, wait until dark and repeat the procedure. It’s important to note that yellowjackets, like all bees and wasps, are essentially beneficial. As long as their nests are not in areas close to the house where you or your family spend time, they should just be left alone and tolerated. But if they are in your daily yard enjoyment zone, then control is likely in order for personal safety!