Bees vs. Wasps
As such, the diet of yellow jackets is like that of most other wasps, except perhaps the bald-faced hornet, which is known when necessary to eat its own. While wasps survive on spiders and insects, bees tend more towards flower nectar and pollen. Only bees manufacture honey in the nest.
Typically, yellow jacket wasps will build their nests underground, in existing hollow spaces. The entrance to their nests is usually small and inconspicuous, but fiercely guarded. It's easy to stumble into the proverbial hornet's nest, or yellow jacket nest, because unlike those of other species that hang in trees and in house eaves, these can be literally tripped over.
A Member of the Social Wasp Family
Social wasps are by definition species that produce a colony. They start over each spring with just a single, fertilized yellow jacket queen. The nests of yellow jackets are built out of paper, masticated by worker bees from wood, paper, cardboard and other materials.
Although wasps can be seen as pests, their dietary habits keep caterpillar and insect populations in check. Most yellow jackets scavenge live insects, but the western yelllow jacket tend to prefer dead insects. Even though yellow jackets may sometimes feed off the nectar of flowers, they do not like bees pollinate. It is simply used as another food source.
Western yellow jackets are also the only one to feed off garbage. But like all other yellow jackets, it is both a predator and a scavenger, and it is that latter tendency that makes it such a pest at picnics.