I think I'll give wasp trap a try. I'm allergic to the things and don't like them at all. I've seen the bags of water hanging up to scare off the flies. Lots of places around here have them. I don't know how well they work as you still see flies. the best thing I have found for flies is a fly trap they sell at walmart and home depot. It isn't poisonous but has some kind of attractant in it. Hang it outside away from the house. We've been using them for several years and it is amazing the amount of flies they attract and trap. OUr dd and dsil had horses for years and they used them in the barn areas.