That’s right. There really is a way to control your fly problem simply, naturally, and successfully. You’ve heard of Three Coins in a Fountain? Specifically, drop four or five copper pennies into a plastic bag half-filled with water, zip it shut, and then place or hang the bag where you want to cut down your fly traffic.
Don’t shake your head so cynically – try it first – and you’ll join a long list of believers, including horse owners, on Google and the Web who have seen their fly problem go from the hundreds to a handful almost overnight.
Why does it work?
It’s all in the reflection: When you have millions of molecules present, like in that clear, plastic bag, it creates its own prism effect. Flies have “compound eyes,” i.e. they see multiple images (whereas we see only one), but compound eyes cannot focus, so flies also see blurry images. To our winged little predator, that bag of water and its copper pennies appear, as one Google commenter described, like “a zillion disco balls,” reflecting lights, colors, and movement in a dizzying array.
Flies prey on us, and our horses, but they are also prey for other insects, birds, and animals. So...faced with approaching our plastic bag (a confusing, potentially dangerous object) or simply flying off to find an easier, safer meal elsewhere, the fly opts for what’s behind Door Number Two.
No chemicals. No pesticides. No big expense from our barn budgets. Just no flies. And the solution works until the bag, for whatever reason, breaks; but hey, it’s easy to put together a new one. So, when it comes to fly control this summer, this is one tip that’s really like “pennies from heaven.”