You shouldn't have to worry much longer. You're far enough north that the weather will make it's own change very soon. Once you get your first real frost, then most of the flies are gone.
I've got close to 2 months before the first real keeper frost here. But thanks to your help - at least I know how to take care of the problem next year.
FR is not just for conservative news - it's for information exchange!!!!!
Both are good things.