Answer: I think we need to figure out why you are seeing so many in one area, and eliminate that, rather than just trying to chase them away. It's unlikely that soil would be the culprit. Mosquitos are drawn to non-moving water sources, where they breed. Do you have any standing water, a bird bath, a pond with a still surface, rain water that stays in the bottom of a container, etc.? (Also check over the fence at your neighbors. Some people allow their swimming pools to become stagnant swamps, which are considered public health issues because mosquitoes carry West Nile Virus. Or perhaps they have a small pond or other still water source and are unaware that mosquitos are breeding.) As for the flies, do you mean regular black houseflies, little flying gnats, or something else? House flies are often drawn by rotting organic matter, such as uncovered garbage cans or pet debris. (Again, check your neighbors!) Please send another email with a description if not house flies. As with my previous response, that many flies should attract some birds and lizards to eat them, but I understand it is annoying.
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