We have had serious problems with yellow jackets trying to get into the
hives (only in the fall). Here in Ohio, I must put on entrance reducers no
later than August 1st because of them. I did learn one interesting thing
about them. Yellow Jackets love sugar, but in the fall they actually prefer
protein snacks. So we bait the yellow jackets traps with a bit of
hamburger. We also put the full traps in a large Ziplock bag & freeze it
overnight to be sure all are dead before emptying the trap. Don't want one
of those mean things near my hives!! Linda in Southern Ohio.