I've been having major problems with my backyard oasis. The pool area is landscaped, and backs to towering trees: oaks, maples, and poplars. This year, we have had an infestation of cicada killer wasps. They are bothersome, but harmless, and mostly active in the morning, before we are out by the pool. They leave mounds of dirt from the tunnels they excavate in the lawn and landscaping. Their numbers seem to be declining now, but now we have an infestation of flies which is even more of a nuisance than the cicada killers. My web research suggests that the flies are a natural parasite of the wasps-- or, at least they like to feed on the dead cicadas the wasps drag into their burrows. One dead cicada can host 50 maggots-- so you can imagine the population explosion of flies we have had. The flies really put a damper on a party we hosted last night. The best we could do was use fans to try to keep the flies off the food.
Has anybody else had this problem? What did you do? I am thinking that I must aggressively treat the wasp burrows with insecticide powder next year. Any other suggestions?