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How To Control Flies On The Farm

For proper fly control and to reduce the fly population in a horse barn and barnyard, you have to have the right tools in your arsenal. There are many methods of winning your war against flies, and your horses will love you for your efforts!

To prepare for battle, here are some key fly control weapons designed to kill flies at their various life stages.

  • Traps do a great job of catching adult flies. Two basic types of traps exist on the market, each designed to attract a different kind of fly. Stable flies are attracted to their traps visually. House flies are attracted to their traps by odor, which can be fairly offensive to humans. Both types should be hung outside, away from your barn, near potential fly breeding locations. If you hang traps inside your barn, you'll actually invite flies in. Generally, traps should be hung less than four feet from the ground, but be sure to follow manufacturer's recommendations for your trap to achieve the best results. You may also want to test various sites on your property to see which locations capture the most flies.

    Note: Sticky traps and tapes without lures catch flies when they land to rest. These can be hung successfully inside a stable, but be aware that you may also inadvertently catch small birds, bats and beneficial insects such as dragonflies.

  • Misters and space sprays, such as the Country Vet Dispenser, provide quick knockdown of flies and other insects within your barn. This battery-operated dispenser is inexpensive and easy to install, and it releases insect killing insecticide according to a built-in timer.

  • Any insecticide that kills stable and house flies may also kill your fly predators.

  • You may find it necessary to rotate different products throughout your fly season. A trap or spray that works in one area during the spring may not be as effective in the same area in late summer.

  • See How to Protect Your Horse from Flies for a variety of suggestions to keep your horse comfortable.

Actions to Take to Reduce Fly Populations
In addition to the products you can purchase for fly control around your property, you can also take these significant steps to create an unfriendly environment for them.

  • Because flies need warm, moist breeding grounds in which to lay their eggs, remove all decaying organic matter from your property. Piles of rotting leaves, grass clippings, decaying fruit or vegetables from gardens all provide an attractive environment in which eggs can be laid.

  • For the same reason, maximize heat in your manure compost pile by keeping it piled vertically as much as possible rather than spread horizontally. Turn your pile to introduce oxygen, which is necessary for decomposition. Add lime to speed up decomposition, and make sure your manure pile stays slightly damp. Increased heat makes your manure pile a less attractive breeding area for flies. If it becomes hot enough, all but the outer edge of your manure pile will be too hot to allow flies to lay eggs. You can also cover the manure piles with black plastic to further increase heat.

  • If you spread your manure on your property, do it thinly (less than 1/2 inch thick) so that the matter dries quickly before it can become a fly breeding ground.

  • Remove fly resting areas near your barn and pastures by keeping grass and weeds cut short. Flies rest on long grass to escape direct sunlight.

  • Solve any drainage problems on your property. Remove moisture and debris that accumulates around watering troughs and level areas where puddles occur. Make sure your hoses and pumps don't drip as the moisture there will attract flies.

  • Clean feed tubs, mangers and areas where horses eat to avoid accumulating crumbs and moist, decaying food waste that becomes attractive to flies.

  • Use ceiling and portable fans in your barn to keep the air moving. Circulating air is difficult for flies to navigate and it inhibits their ability to land on your horse. Stall fan holders enable you to mount a portable box fan at the top of a stall at a 45 degree angle so that the air streams down over your horse.

  • Keep stalls free of manure and urine as the odors are attractive to bothersome house flies. Products such as Odor-No-More and Stable Fresh can help you keep your stalls even fresher and more odor-free than regular mucking alone.

  • Encourage natural insect predators —birds and bats— to set up residence on your property by hanging bird and bat houses.