As horse owners, we often believe we are destined to “put up” with flies and insects. In many parts of the Northwest, mild winter weather causes a long and serious fly season, often lasting from March into late October. Other regions have shorter but notoriously ferocious biting insect seasons.
Horses can expend a tremendous amount of energy stomping and swishing at irritating pests that can harbor disease, cause eye infections and inflict painful bites. Since our domestic horses can't roam and escape insects like their wild counterparts, here’s a few strategies to help keep them fly-free and happier this summer:
Cover your manure pile. Flies are associated with fresh manure and not the composting process. A simple cover or tarp on manure piles and compost bins helps reduce breeding habitat for insect pests and speeds the composting process.
Keep it dark. Some insects such face flies, biting midges, and deer or horse flies do not like to enter darkened barns or stables. Keeping lights off and stabling horses before and during dusk (for biting midges and mosquitoes) or during the hot part of the day (for deer and horse flies) can help them escape heavy attacks of these miserable creatures.
Create air circulation. Biting midges and mosquitoes tend to be poor flyers. Good ventilation and a fan safely placed outside a stall to create air movement helps reduce pests in the barn.
Graze on dry ground. Whenever possible, graze horses on higher, drier pastures at the beginning of the summer to avoid creating muddy areas. Save lower, wet pastures (which harbor mosquitoes, deer flies, horse flies and biting midges) until these areas dry out.
Pick up manure and harrow pastures. To help to further eliminate fly and mosquito breeding grounds, pick up manure in paddocks and harrow (or drag) pastures regularly to break up manure piles. Harrowing dries out manure, making it less attractive for flies as habitat, and helps eliminate muddy areas that harbor mosquito larvae.
Invest in fly masks and sheets. Most every horse owner knows about the wonderfully safe and effective method of fly management using a fly mask. Some masks protect the eyes while others also protect ears and jowls. Fly sheets, cool, open-weave, light-weight, mesh blankets can be quite useful at keeping pestering flies off a horse’s body. Fly boots are also available to protect a horse's legs.
Bait and trap adult flies. Several types of simple insect traps can be useful for reducing the flying insect population. The cheapest and easiest are sticky traps. Fly paper ribbons, brightly-colored sticky tubes and rolled sheets can be hung in the barn where they are out of contact with swishing horse tails, pets and birds. These traps may or may not have an attractant (an embedded scent) which flies seek out.
In addition to sticky paper, several specie specific brands of pesticide-free bait bags and jars are on the market. A food or pheromone attractant is used in these that activates when dissolved in water. Lured by the scent (and perhaps the color), flies (and yellow jackets) enter the trap through the yellow cap top and are either drown in the water or cannot escape. You can also make your own fly bait jars cheaply and easily with an old mayonnaise or similarly sized jar with several holes punched through the lid. Put a few pieces of raw hamburger or fish on the bottom with a couple inches of water.
Make sure to place traps with attractants away from your barn and horses so that flies and pests aren’t drawn into the barn. The downside to bait traps is they are smelly; another good reason to locate them away from barn areas.
Enlist the help of predators. While it may be too late in the season to totally eradicate your fly population using fly predators, they can still be very helpful in lowering populations. Fly parasites, or predators, are gnat-sized, nocturnal wasps which lay their eggs in the developing pupae of flies, thereby reducing or nearly eliminating the fly population. They do not harm humans or animals in any way - in fact, you won't even notice their presence. There are a number of internet-based companies that sell fly predators and quickly ship them to you by mail.
Plan now for next season. Make plans to be pest-free next season by noticing where you have pest problems now. Increase your population of good predators by researching and putting out nesting boxes and creating habitats to lure them in. Mark your calendar to remind yourself to start a fly predator program next spring, before populations of flies take hold.
In pest management, we often err by approaching most insects as pests. According to the Xerces Society, a forty-year-old nonprofit organization that works world-wide to conserve habitat for beneficial insects, only about two percent of all insects are considered pests and many insects prey on each other; insects would rule the world if that wasn’t the case.
The key point to keep in mind when trying to manage insects is to strive to reduce habitat where they live and breed, which is mud and manure. Other odors that attract flies, such as garbage, sweat and urine can be minimized by emptying garbage regularly, rinsing sweaty horses after exercise, and controlling urine odors in stalls and paddocks.
What methods do you use to keep your horses fly-free? Leave a comment.