Shoo fly!

When warm weather hits, flies' feeding frenzy on field-dwelling and the barn-living mammals begins. They land and swarm, pester and annoy, bite and bother, but despite their animal victims' bucking, snorting, tail-swishing and mud-wallowing, the wrath of the vicious little vampires is largely unaffected.
Certainly, we humans have little patience for houseflies, stable flies, horseflies, deer flies, horn flies, and all their cousins.
The winged pests bother us by accidentally drowning in our coffee cup. They perform annoying, low-altitude fly-bys in our faces, and they rudely claim our summer picnic sandwich as their own-effectively pulling up a chair and helping themselves to that next bite of tuna on white we'd been planning to enjoy.
A fly population is an unpleasant vibrating nuisance for humans; for horses and other animals, life with flies is exponentially worse-it's painful.
On four-legged beasts, flies insinuate themselves onto, under and around every inch of grazing animals' bodies. They swarm the eyes, land on legs, and invade the ears. And then those bloodsuckers bite. (Imagine receiving hundreds of hypodermic needle pricks at the same time, all day long!)
Animals stomp, shudder, shiver, shake, roll, and scratch to find relief from the flying parasites' unceasing torture. Human intervention in the form of pesticides, repellents and anti-fly stable management techniques is required to provide some measure of relief.
According to Orange County Extension Agent Steve Hopkins, between resistance to chemicals and plentiful pasture growth, and wet weather, the 2009 fly season is one for the record books.
"Flies are bad this year. I have had more reports of pinkeye [conjunctivitis] in livestock then normal," Hopkins said. Opportunistic flies, who land and feed near animals' eyes, pick up the infection and carry it over to grazers' herdmates. And with their appetite for all things smelly, repulsive and altogether revolting, flies are lured in even greater numbers to four-legged animals' goopy, weepy infected eyes as infections spread throughout the herd.
The best approach to managing fly populations and protecting livestock is an all-out, full-on, no holds barred assault on flies.
"Flies can build up resistance to insecticides so if you use one insecticide last year use a different one this year," Hopkins explained. "Also, using multiple methods to control the flies helps. Fly tags, pour-ons, sprays, face mops with fly control, manure handling, and premise sprays are all methods of control that can be used."
Naturalists and ecologically-conscious horse owners and barn folk may consider the prospect of spraying pesticides over every inch of their equine friends to be an unforgivably toxic method of fly control. Folks who favor a poison-free approach to fly season have options.
There are mail-order fly predators-a teeny variety of wasp that feeds on fly larva, destroying the population. Supply stores' shelves this time of year contain sprays and ointments made of non-toxic, all-natural fly repellents. Ingredient lists on the labels of these bottles contain marigold extract, thyme oil, citronella, and clove oil.
Other methods that don't require spraying chemicals all over the ground or misting animals from one end to the other include traps and fly strips. These lure the annoying rascals to their deaths by attracting them with an array of stinky substances-some are easily detectable to humans as the odor of a rotting carcass, others are slightly more subtle. Once the flies are drawn in, they find they're either trapped in a container, unable to escape, or they're firmly affixed to paper with an inescapable sticky coating.
Conventionally, chemical weapons are used in the fight against the fly. Containing pyrethrin, permethrin and piperonyl butoxide, sprays and wipes reliably work to repel flies and some preparations will kill them. These products go directly on animals, or are used as a premises spray.
Either way, there are basic barn maintenance methods that can go a long way in thinning out the flying pest population for horses and others. Most methods are based on the simple premise that if flies can't breed and feed, they won't maintain much of a presence.
Tractor Supply Assistant Store Manager Brecken Gutshall recommends a multi-pronged approach to fly control which includes eliminating fly attracting factors around the barn and using traps as well as sprays to keep flies of all kinds off of horses and other livestock. Gutshall owns horses, too, and practices what she preaches. On her own horses, Gutshall said she's tried a number of methods with varying degrees of success.
"The best thing you can do is make sure all your feed [containers] are sealed and keep your manure pile far away from the barn," she said.
Gutshall's horses get a break from flies on their faces by wearing mesh masks, she said, and she applies a combination of fly spray formulas to keep comically oversized (but particularly aggressive) horseflies and those mean green-headed rascals from divebombing her horse while she's riding.
Nasty as it is, flies like manure. And grazing animals tend to produce rather a lot of it. Fend off a fly ambush by removing manure from stables and sheds, and putting it as far away as possible. Remove standing water and wet hay, and clean up feed spills.
Northern Piedmont Agricultural Research Center Superintendent Dave Starner said standing water, rain-sodden hay and other soggy areas in animals' environments can lead to fly proliferation. Specifically, wet areas are a great place to raise your kids, as far as flies are concerned. Squishy, muddy, and marshy areas make for great fly egg incubators.
"It stands to reason that with more moisture, a greater number of larva can survive," Starner said, which means more flies reach adulthood, creating a flourishing fly family tree.
They're mean little vampires, that's for sure, but a stake through the heart and other traditional measures for dealing with the undead don't apply.
"There is no silver bullet for fly control," Hopkins said.