Has your barn been overrun by flies? Don't get bugged. Get even. It's time to declare war on these winged pests.

The first line of defense in this battle begins with knowing your enemy. There are several hundred species of flies that plague horses and their owners. They not only cause great discomfort in their constant buzzing and biting, but they also spread infections and diseases. Horses attempting to escape the buzzing bombardment of these pests may rest and graze less, which could affect their overall health, weight and safety.   

These six flies are common enemies to your horse:

2) Stable fly - Is a biting fly that feeds on the horse's blood. Known for incessantly biting at the legs, causing the horse to stomp, squirm and flick its tail.

3)Face fly - In addition to feeding on wounds and secretions around eyes and nostrils, this female fly also uses its sandpaper-like tongue to abrade the horse's eye tissue to stimulate tear flow, which can lead to infections and blindness.

4) Horn fly - Smaller than the house fly, this biting pest prefers cattle, but will attack horses, too. They can fly up to ten miles and will stay with the same animal throughout its life.

5) Bot fly - lays its sticky eggs on the horse's hair, around and inside its mouth and throat, also on the inside of its legs. The larvae hatch in the mouth and will migrate to live in its stomach and intestines, causing poor health and possibly death.

6) Gnat - These teeny flies have painful bites that causes itchy skin break-outs, causing painful sores and patch hair. They attack primarily at dusk and dawn.

Know the Enemy's Camp

Flies generally need a warm, moist, breeding ground to lay their eggs. Decaying organic matter (such as rotting leaves, grass clippings, decaying fruits and vegetables), manure, standing water, rotting hay, feed mangers or tubs and trash are common breeding spots.    

Most fly life cycles last up to 8 weeks from egg through adulthood. Some females can lay several batches of 40 to 80 eggs.     

Defeating the Enemy

The best defense in controlling fly populations is a good offense. Begin with these steps:

2) Remove and manage manure - A meal of fresh manure is considered fine dining for these pests, so clean stalls and pens regularly to remove manure and urine and their odors. Move manure to off-site locations or away from barn at least once a week. Cover manure piles with a tarp and treat with larvicides. Since high heat deters flies, manure composts should be piled vertically and covered with tarps to maximize the heating process. Turn piles often to introduce oxygen and add lime and water to speed up decomposition. In addition, when dragging fields where horses feed, spread manure to less than one half inch thickness, to dry it out faster and decrease possible breeding grounds.

3) Use air to your advantage - Place fans strategically inside barn to circulate air more efficiently, making it difficult for flies to hang around or land on horses. Stall fan holders maintain a continual flow of air directly around the horse. Position fans to direct air down and out barn doors to keep flies from entering.

4)Keep food covered - Cover all feed containers and keep areas around food sources clean. Keep garbage enclosed tightly and empty regularly. Install screens on feed and tack rooms and box stalls.

5)Keep it dark - Some flies avoid dark areas, so provide shade and turn off barn lights to deter flies and other insects.

6) Watch the neighbors - Horses pastured close to other livestock risk becoming victims of the horn and face flies. If possible, keep them a safe distance.

Attack Arsenal

Eliminating breeding grounds is important in winning the battle with flies. However, after taking the steps listed above apply these weapons: 

2) Barriers - Include lightweight outer sheets, masks and boots to cover and protect skin and sensitive areas from biting flies.

3) Fly traps and sticky paper - Uses bait or attractants to capture and ultimately kill adult flies. They are considered generally safe since there are no insecticides involved. Different traps are used for each insect species, so know which species you are trying to control. Traps should be placed outside the barn near breeding grounds. Sticky paper can be placed on walls where flies generally rest after feeding. Unfortunately, sticky paper may also catch dragonflies, bats and even some small birds.

4) Barn spray systems and residual insecticides - Good for killing flies, mosquitoes and other insects using natural or commercial insecticides. However, some commercial insecticides can also kill beneficial insects such as spiders. The system delivers a fine spray mist at regular intervals. Residual insecticides are applied to walls, ceilings, and rafters where flies rest. Cover food and water sources before applying commercial products.

5) Incorporating fly parasites - These tiny, non-stinging wasps are a great tool for biological warfare against flies. They seek out and lay eggs in the fly pupa right in their breeding grounds and then feed on the fly larvae. These parasites are typically nocturnal, so they are rarely noticed by horse or human. Many commercial companies sell them by the bag to place around the property near breeding grounds. You may need to introduce them several times during horse fly season which runs from April to September.

6) Feed-throughs - These insecticides are mixed with feed and pass through the digestive system making manure toxic to developing maggots.