In the last couple of days I've killed so many wasps. We have a very low eaves house and they have made a nest behind the bargeboard. There have been too many flying around to spray during the day, but in the dark just after sunset when they are all inside, it’s spay time. In the past 2 two there have been over 200 on the ground outside and another 100 in the lobby as they have found a way from the cavity though the blockwork to come up behind the skirting but the are drowsey even a four year old can kill them – hitting them several times before they stop twitching. The good news is this year we were not plagued by flying ants, it was the neighbours turn to run inside one the summers evening.