Basic Biology of Yellow Jackets
Yellow jackets are a species of social wasps. Most species build their nest underground. They are commonly build in abandoned animal dens. However, some build them in wall voids. Nests may contain thousands of members and they are usually very aggressive. The nests only lasts one season because only the queen survives winter.
Often the ground nests are found while mowing the lawn or in mulch beds and can become dangerous. Sometimes you get a warning that they are present when they bump into you without stinging. It's best to clear the area quickly.
If you discover a ground bee nest in your yard, our Stinger Stopper TM program is a good fit to safely tackle the nest.