I live in Milwaukee and the winters are usually cold enough to kill "mother hornet". However, we have had several mild winters and now we are invaded by Hornets in the peach trees. Anybody know of a spray, trap, etc that is effective against these "darned" painful things.
I can't believe one of our fruit tree folks didn't jump on this one (I *know* they're not out picking fruit this time of year, lolol.)
I don't know the answer off-hand, but I'm guessing that maybe your local extension agency would be able to recommend a spray or other treatment; or you might try contacting Gardens Alive! in Indiana. (Now I know a lot of people have strong feelings about this company, so if you're in the "dislike/hate with a passion" camp, disregard that advice ;o)