Once the scourge of Maine in the spring and fall, black flies have become a constant the past few years. These nasty pests are tiny, black, fast moving flies with bodies maybe 1/16″ long. They begin appearing in late May or early June and last through the first deep frosts. Black flies hatch in fast running water. It used to be that during the high summer the rains slowed down, Maine dried out some and the black flies went away for a few weeks respite. Thanks to the global weather changes, the effects of which I have witnessed in this area in my lifetime, our weather has become much more rainy. And our black flies are now a permanent summer feature.
Black flies form clouds, what can seem nearly solid masses. They encircle your head, flying into your eyes, nose, mouth. They land on your hair and work their way down to bite your scalp and feed on your blood. The bites cause intense itching that can last for several days and significant swelling. The flies will bite any exposed place on your body but prefer the head and face. For horses and other four-footed animals, black flies are a torment. They crawl into ears or land on the underbelly, biting in huge numbers until the skin is raw and bleeding. This can happen in a matter of an hour. For horses to graze in peace, a fly mask and regular applications of insecticide are crucial.
An essential for any tack box, a good fly mask covers a horse’s eyes and ears. It is made of a very fine plastic mesh, preferably black or white, that the horse can see through but flies can not penetrate. The masks protect ears from black flies and eyes from larger face flies that can cause pink eye. Fly repellants are also entirely necessary to protect horses. Most repellants only work for a couple hours or less, no matter what the product manufacturer claims. Some repellants don’t work at all. My choice for a spray on fly repellant this year is Bronco E. It seems to last about 2-4 hours, depending on the flies that are present. I spray the horse’s entire body, except the face, which is covered by the fly mask. Special attention is required for between the front and hind legs, the neck and chest, and along the mid-line of the belly. These are areas all flies aim for.
In the photos of Maddie and Vista, swarming masses of black flies can be seen. Yet the horses are able to eat in comfort because the flies only hover and do not land.