My new abode has flies. Little small flies that burrow in the ground. When the sun hits that area of the house, these little black flies swarm. There are hundreds of them, they come out of little holes in the ground. I have never seen this before but it is horrible. I bought some Ecologic Insect Killer that is supposed to kill on contact but that is not working. I need something non-toxic to children and pets. There are small children plus two dogs so whatever is used needs to kill these flies but be harmless. Diatomaceous earth was suggested to kill these flies but since they are in holes would it be beneficial to dig up the area (unhappy landlord) and get it right into the heart of the nest or would a dusting over the area be okay. I know when I was spraying my Flying Insect Killer made with Lemon grass they were coming out in droves trying to avoid the smell, dropping from being stunned but not dying. It is a huge ground infestation.