1. Eliminate the sources of the fly infestation
All fly infestations can be traced back to a source of unprotected organic material. The usual culprits are improperly handled garbage, animal droppings and dead animals. There are tons of different species, all of whom enjoy feasting on different things, but their preferred main courses are not so diverse that we need to immediately differentiate them unless you are unable to remove all of the possible food sources as outlined in this article.
Fly-food and breeding grounds
The key to reducing any fly population is to identify and eradicate the feeding and breeding grounds and as luck has it, flies lay their eggs in their food. Follow along as I walk you through some of the most common attractants and explain what you can do about them.
Garbage and decaying organic matter
Many filth fly infestations are the result of improperly handled human wastes. Perform a thorough inspection of every nearby area that collects organic waste such as garbage cans, dumpsters, and compost heaps. Flies will feed and breed in any of these places assuming the waste is moist and accessible. Make sure all garbage is bagged and stored in garbage cans with tightly-fitting lids secured to the cans. In the case of metal trash cans, a pair of bungee cords can be threaded through the handles and over the lid to keep it secure. Dumpster’s should have hinged lids that are kept closed and compost heaps should be screened off or contained in tubs. Look around for loose organic materials and spills.
Inside of your home, organic waste should be drained and wrapped in newspaper prior to throwing into the trash. The paper will help to dry out the waste - flies can’t breed in dry waste. Make sure your trash can has a tightly fitting lid, and tie the bag completely shut before transferring to an outside can for trash pickup. If you have flies breeding in your drains, a commercial drain cleaner will remove the organic film that they are breeding in.
Animal waste
There’s nothing flies seem to like more than a warm log straight from your dog… Any animal waste should be picked up and immediately buried or flushed down the toilet.
Decaying flesh
Dead and decaying animal flesh can also breed flies - not to mention the horrible smell and appearance. Search around for dead birds, rodents, squirrels, and road kill. If you locate an unfortunate critter, use a shovel to move it and bury it at least three feet deep to keep any flies that spawn from it from reaching the surface.
Other attractants
Some varieties of flies feed on the blood of living creatures. These are a little harder to battle since you can’t completely eliminate their food source (you). Others lay eggs in other insects and earth worms. These types of flies are better battled with traps and physical barriers like screens and netting.
2. Fly management
If the source of the flies cannot be effectively eliminated then you may want to take more direct countermeasures. This section will show you how to fly-proof your home and kill them off with traps.
Fly-proofing your home
The process of fly-proofing your home is pretty straight forward, the two major entry-points for flies are doorways and windows. Windows can be protected by adding screens that fit tightly into the opening, leaving no gaps for flies to enter around the edges. Repair damaged screens with a dab of silicone caulk or screen patches (available in most places that sell screen windows). Doorways can be protected in a similar fashion with screen doors, or by keeping the door shut as much as possible.
Beaded curtains also work well for keeping flies out of an area. The better the beads interlock without gaps, the more effective they will be.
Fly repellents
Zip-lock water bags
Many people swear that a zip-lock bag filled half-way with water and attached over entry-ways will repel flies. No one yet knows how or why it works, but there is speculation that it has something to do with the way the moving water refracts light. If you have tried this please use the tips form at the bottom of the page to share your results with the rest of us.
Personal insect repellents
Repellents containing DEET (Diethyl-m-toluamide) work well at repelling all sorts of insects including flies. Use these rubs and sprays on your clothing rather than directly on the skin, and never on your pets.
Citronella torches and candles
Citronella oil is derived from citronella grass. It is used in perfumes, soaps, and insect repelling candles and tiki torches. These candles and torches are marketed mainly as mosquito repellents but also work to repel flies.
Fly traps
Fly traps have a dual purpose. If used intelligently they can dramatically cut down on the number of flies that you see by using them to strategically encircle your desired no-fly zones. They are also useful for monitoring the fly population as you work to eliminate environmental causes so you can get some feedback on the effectiveness of your actions.
Fly swatters
Not so much a trap as an offensive weapon, the common fly swatter is an effective tool for hunting down any particularly annoying flies that have made it through the perimeter. Find one at your local department store or supermarket.
Fly paper
Fly paper is efficient at catching flies, but is horrendously ugly. Use it in direct sunlight for the best results. Fly paper is also good for catching undamaged specimens for identification. The glue is very difficult to remove from hard surfaces and nearly impossible to remove from clothing so be very careful during setup and removal.
Fly traps
Most fly traps work by placing an attractive bait in a location from which the brightest light leads right into a trap. After feeding on the bait, flies will normally fly towards the brightest light source and get stuck inside of the trap. These can be purchased or made at home and work very well. Here are some things to keep in mind about these traps:
The bait will need to be kept moist, so purchasing a trap that has a water reservoir can cut down on maintenance.
These traps will also need to be periodically cleaned so look for one that opens easily.
A mixture of molasses and cornmeal makes an effective bait that will not support fly eggs.
Place these traps up-wind of suspected areas of infestation.
UV Bug lights
Also known as bug zappers, these traps use an ultraviolet light to attract insects to an electrified grid where they are promptly charred out of existence by a high voltage current. They work excellently for reducing the overall insect populations when they’re habitually left on over night but they have the draw back of also killing beneficial insects. Small and portable indoor versions are also available