Matt writes
All insecticides can only kill any insect if the insect, or fly in this case, comes into contact with it. When treating for flies you should apply the insecticide to any surface that the flies typically land on. Once they land on the surface they will pick up the product on their body and eventually be killed. It is not an immediate kill, but depending on how long ago the surface was applied and how fresh the product is will determine how long it takes for the fly to die. We do have very effective fly control traps that you may want to try also.
Answer last updated on: 07/30/2011
