House Flies

travel as far as 20 miles to find food and ovipositional sites.
Management
There are four basic principles of pest management important in controlling house flies sanitation exclusion nonchemical measures and chemical methods. These are listed in order of lasting effectiveness.
Sanitation
Flies cannot breed in large numbers if their food sources are limited. Do not allow such materials as manure garbage grass clippings weed piles or other decaying organic matter to accumulate. Keep trash cans clean and tightly covered. Be careful not to wash garbage cans where the rinse water might drain into the soil flies can breed in soil full of organic matter. Dry out maggoty garbage or dispose of it in flyproof containers or landfills.
Exclusion
Flies can be kept outside of homes by the use of window and door screens. Make sure screens are tightfitting without holes. Keep doors closed with no openings at the top or bottom. There should be no openings around water or gas pipes or electrical conduits that feed into the building. Caulk or plug any openings. Ventilation holes can be a way for flies to enter a building. Ventilation is important to maintaining adequate air circulation within the building but screening must be used to exclude flies.
Nonchemical Measures
The use of such devices as ultraviolet light traps sticky fly traps fly swatters baited fly traps etc. can eliminate many flies from inside a home. A fly swatter is an economical control method for the occasional fly.

Chemical Control
Exterior applications of insecticides may offer some relief from infestations where the task of completely sealing the exterior is difficult or impossible. Applications should consist of a synthetic pyrethroid i e. deltamethrin cyfluthrin lambdacyhalothrin cypermethrin sumithrin or tralomethrin and should be applied by a licensed pest control operator when flies begin to appear.

Unfortunately because insecticides are broken down by sunlight the residual
effect of the material will be greatly decreased and may not kill flies much beyond several days or a week. If flies are numerous inside your home you can use a space spray aerosol labeled for flying insects. Most space sprays contain pyrethrins for quick knockdown. Aerosols give temporary relief however. If you have many flies inside you would be wise to find out why they are there and take steps to relieve the problem through sanitation and exclusion.
Warning
Pesticides are poisonous. Read and follow directions and safety precautions on labels. Handle carefully and store in original labeled containers out of
the reach of children pets and livestock. Dispose of empty containers right away in a safe manner and place. Do not contaminate forage streams or ponds.