So they do serve a purpose yellow jackets eating a Japanese beetle larvae

While digging a hole to plant a camellia I noticed several yellow jackets flying around the freshly turned earth. I thought I dug into a nest but soon realized after not getting stung this was not the case. Instead the little winged devils where eating exposed grubs and other bugs I was always told their diet changes from protein to sugars during fall to get ready for winter but I guess they still need a little protein too.