WanMan, I confess, I hadn't even thought about the threat posed by wasps. I was thinking of bees robbing bees.
As far as wasps go, their populations are generally very low in the early spring and summer. Their numbers build up as the seasons progress and generally become problematic toward the end of the summer and into the fall.
But I can't say that I know about all the areas where there are exceptions, so take my quoted rermarks with some reservation.
This afternoon I had to take my weather station down from its pole because it had become plugged up and wasn't measuring rain. When I had it on the ground and looked it over to clean it up a bit, I found a wasp's nest in the area below the rain bucket. Cleaning it out I must have destroyed about eight wasps. Fortunately, the weather was too cool for them and they couldn't fly. I did them all in without a single sting. Had I not found them, they probably would have been the starting queens of new nests when the warm weather arrives.