Many horse owners are frustrated by the fly repellent market because of confusion over product effectiveness. Some products, particularly the natural ones, are designed to repel insects — to keep them from landing on and biting your horse. Repellents work by coating the hair and skin with a substance — usually a fragrance — that is unacceptable to the insects (although usually not to us) and can even upset their sense of direction.
The other part of the market, commonly the chemical solutions, includes products designed to kill flies/insects. In order be effective, the fly must be touched by the substance — not an efficient way to use fly sprays, but if there are flies around when you use the product you’ll see them become disabled and die — or it must somehow come into contact with the poison. This means that flies may still land on your sprayed horse in order to touch or ingest the poison before the substance is effective. This creates confusion among horse owners in that the fly still torments the horse somewhat, but the result should be dead flies.
There are thousands of species of horse-tormenting insects. You may need different products for different insects, and different products may work for you during different insect seasons or from year to year. Each horse’s body chemistry and sensitivity is different. Some horses will attract more flies just as some will be more bothered by them. Similarly, a repellent may work on one horse but not on another.
What We Want
We want a product that:
Either keeps flying insects off the horse or at least limits their landing time and keeps them from biting.
Complements our existing insect management program.
Poses minimal hazards to us, our horse, and the environment.
Is easy to apply.
During our testing, we watched carefully before, during and after application, including coming back at different time intervals to check the results. In some cases, flies did not land. This is the kind of product we want while we’re working with the horse, grooming, and for relief on those days when the flies ceaselessly torment the horses in their stalls or pasture. This relief never worked as well or as long as we wanted, but we were able to detect differences among products.
In other cases, after we applied the product, insects would land but only briefly. We consider these products effective. Sometimes flies would land and work among the hairs without seeming to bite (the horse didn’t swish or stamp) and then fly away — we hope they went away never to return. This situation is acceptable to us for pasture situations if it means we’re reducing the fly population.
And, in some cases, the substance didn’t seem to “work” at all — the flies still landed and bit en masse.
Nearly all the products we tested come with a money-back guarantee, which we like. But before you send any of these products back, be sure you were following the particular label directions exactly. Application directions differ widely. Several products in both natural and chemical categories require repeated applications — from twice an hour to every week — and will build repellency over time. While we want relief for our horses immediately, following the label directions (even if it takes more time) and sticking with each product over time maximizes these products’ usefulness.
Experiment with the amount applied and the treatment interval, depending on temperature and humidity, and on how slick and clean your horse’s coat is. In general, the dirtier and longer the coat the more repellent is often necessary.
Experiment with dilutions, if available, to obtain optimum effectiveness. We asked manufacturers of concentrates if we could apply their products straight. Farnam stated that, in the case with Repel-XP, they could not recommend any off-label use. Whitman, with the natural product Clac-86, replied that it was no problem. These answers are in keeping with our understanding of the chemical versus natural products — the natural ones generally are safer to apply more freely.
Chemical or Natural
We compared the products to each other, including natural to natural, chemical to chemical, and across these lines. In some cases, the products combine natural and chemical ingredients, in which case we’ve labeled them as chemical.
There is broad interpretation of “natural” within the industry (as is the case with human products). While we’re comfortable with our breakdown here, the consumer is wise to read the label and ask the manufacturer questions about ingredients in their products.
As a broad generalization, the chemical products tend to be more effective, though sometimes the flies still land (in order to ingest the poison). Since many of the chemicals are insecticides and pesticides, and toxic to fish, we are concerned about their effects on the environment. Some parts of the country have the benefit of fly predators that capture stable flies off horses to feed their young. We don’t want to poison these helpers.
We take seriously product warnings to wash hands and take care in handling the substances. We prefer that the manufacturers clearly state precautions to allow us to protect ourselves; it’s also legally mandated. As in other marketing situations, we believe some manufacturers follow labeling directives more closely than others. We’re happy to look for more environmentally friendly alternatives, if they work as well. The natural repellents tend to have fewer warnings, and we are comfortable applying them more often.
In general, we’d use natural products on sensitive-skinned horses before we’d use the chemical products. If in doubt, try on a small area first. Note that your horse might be sensitive to a particular ingredient that his stable mates tolerate. Allergic reactions sometimes happen when too much or one too many applications occur. If the horse has been bitten by flies and has small open wounds, choose your repellent carefully. Some will “sting” open skin. If reactions occur, bathe him thoroughly and rinse well.
Beyond Fly Repellents
Fly repellents alone won’t solve insect problems. Manure management is a vital part of fly control. Well-cleaned stalls, and those that get picked throughout the day, eliminate fly congregating spots. Regularly dragging paddocks and daily cleaning of sheltered areas or other areas where horses spend their leisure time also serves to eliminate fly breeding areas. When manure is spread and dried it is much less attractive to flies.
When horses stay indoors, automatic insecticide systems and fly traps are helpful. And, of course, fly masks and even fringed brow bands help keep the flies away, too.
All this together adds up to a winning battle, although still never ending. If the horseman keeps after the flies, the flies will tend to go to easier pickings.
While several repellents earned a “superior” rating in our tests, our overall favorite by a nose was Farnam’s Bite Free. For those on a budget, our Best Buy award goes to Bio-Groom’s Repel-35 spray.
If you prefer naturals, Gnat-Away Cream leads by virtue of its unsurpassed effectiveness against gnats. For a more general natural spray, we suggest Flicks. The Best Buy in naturals goes to Equine America’s Citronella.
For specialized use, we suggest Absorbine’s UltraShield on your show horses and Solitude Pour-On as a good choice for your pasture horses.