Fly Control for Your Barn

Contributed by: Valerie Mellema

It’s that time of the year again – fly season. Flies are pesky and bothersome and they can wear your horse out! The constant swishing and stomping and biting can really take a toll on everyone. Here are a few strategies for helping to keep the flies under control on your farm.


The First Step is Prevention

The life cycle of the fly consists of four stages. The egg, larva (maggot), pupa and adult. It takes 2-4 for the egg to hatch and grow into an adult. Adult flies live for 3-4 weeks after that. Of course, depending on the environment, this process can go even more quickly. To really control flies, you have to be able to break down the life cycle at each stage, so a combination of fly control methods is required to really be effective – particularly since they grow and reproduce so quickly!

This means you need to keep manure under control and remove the food source. Flies feed on manure and keeping stalls clean and dry will eliminate a lot of flying insects from inside the barn. But, what do you do with that manure?

Rather than dumping it all in one spot on the farm, it’s recommended that you spread it with a manure spreader across your pastures. Flies like the deep manure and their eggs can’t survive when it’s thin and spread out. The manure will fertilize the pastures, but will also keep piles to a minimum. For the manure already in the pastures, using a pull behind chain harrow to spread out manure piles will help reduce the reproduction areas of the flies. This helps the manure break down faster.


Fly Predators

These are little packages of parasites that you sprinkle in your pasture. The fly parasites don’t bite or sting you or your animals, but they are a natural enemy of flies and will kill the flies in the maggot and pupa stages, breaking down the life cycle of flies. Fly predators have received tons of great reviews by people who have used them.  People have noticed a significant decrease in flies on their property. It is recommended to sprinkle them along fence lines, wet areas, and areas where there are rotting vegetation and manure piles. 


Feed Through Fly Control

These are supplements or blocks that you feed to your horses. Some supplements are pellets that you add to your horse’s feed. You can also buy a block like a mineral block and the horses lick them and ingest the supplement that way. These are another tool in breaking down the life cycle of the flies. To be effective, it’s important that all horses in the barn receive the supplement. Keep in mind that these do not affect flies that are already adults, but help to prevent more flies by breaking down the reproduction cycle.


Fly Spray Systems

These are full barn systems that spray on a timer, pulling the spray from a large reservoir. It’s similar to a misting system and the heads can be placed in stalls or other areas where flies are a problem. There are pros and cons to these systems. They are great for the area that they are spraying, but when it goes off, you can sometimes feel as though you are being “gassed” out. The spray does have to be refilled regularly and the system maintained. Again, this is a prevention for the area that gets sprayed and won’t have an effect outside the barn.


Fly Sprays and Wipes

Traditional fly sprays that you spray on your horse also help with the adult flies. You can instantly provide knockdown relief just before you ride or after a bath. There are several brands on the market and they all have their pros and cons. There are several that are more natural than they used to be and some are even sweat resistant. For sensitive areas, like around the eyes and mouth, there are several fly wipes available as well. For injuries, fly gels and ointments can help the injury heal while keeping the flies off them.


Fly Bags and Tapes

Catching flies is one way to help reduce them, but it’s one of the least effective methods. Be sure to hang the fly bags away from the barn and away from where your horses enjoy hanging out. Some of them have a rank odor to them as well. The fly bags will attract adult flies and help limit the number of flies available for breeding. Fly tapes work in a similar fashion but don’t catch as many as fly bags.


Fly Masks and Sheets

Fly masks, sheets, and leg wraps are designed to simply keep the flies from biting the horse wherever they are covering. There are a wide variety of options available on the market.

For our East Texas heat and humidity, thinner is better. The fabric options have come a long way since the fly sheet was first introduced to the horse world.

Fortunately, they are a lot cooler than they used to be. It is important that the fit of these items are checked regularly as they can rub or come unhooked, torn, etc.


Air Circulation

Flies don’t like moving area. Ceiling fans and portable fans can make it difficult for them to fly around. Plus, they provide cooling relief indoors when the temperatures are high and can make barn work more bearable.


Back to Prevention

All sorts of barn waste attract flies, from dropped feed to manure to cat food. Make sure that your trash cans have lids and that water buckets are cleaned regularly. Removing the food source is key in reducing nuisance flies.

Do you have trouble with keeping flies at bay? Did this article provide some insight to help you with your current "fly situation"?


Valerie Mellema is the owner of Gray Horse Publishing & Marketing.

She has been in the equine industry for over 25 years and is a published author of multiple horse care books. She is also the owner of Mellema Thoroughbreds, a thoroughbred breeding farm. She shows her OTTB, Mistic Gray, in hunter/jumpers.

You can follow her on Facebook and Instagram.