Here's the idea: Take a ziplock bag, fill it half full with water and put three pennies in it, then zip it shut. Next tack it to an area where you have experienced an abundance of fly infestation. For some reason, the flies take off for other parts.
Ann Says: I tried the ziplock bag and pennies this weekend. I have a horse trailer. The flies were bad while I was camping. I put the baggie with pennies above the door of the LQ. NOT ONE FLY came in the trailer. The horse trailer park had many. Not sure why it works but it does!
Danielle Martin Says: Fill a ziplock bag with water and 5 or 6 pennies and hang it in the problem area. In my case it was a particular window in my home. It had a slight passage way for insects. Ever since I have done that, it has kept flies and wasps away. Some say that wasps and flies mistake the bag for some other insect nest and are threatened.
Maggie Says: I swear by the plastic bag of water trick. I have them on porch and basement. We saw these in Northeast Mo. at an Amish grocery store & have used them since. They say it works because a fly sees a reflection & won't come around.
DJ Says: Regarding the science behind zip log bags of water? My research found that the millions of molecules of water presents its own prism effect and given that flies have a lot of eyes, to them it's like a zillion disco balls reflecting light, colors and movement in a dizzying manner. When you figure that flies are prey for many other bugs, animals, birds, etc., they simply won't take the risk of being around that much perceived action. I moved to a rural area and thought these "hillbillies" were just yanking my city boy chain but I tried it and it worked immediately! We went from hundreds of flies to seeing the occasional one, but he didn't hang around long.
I'm going to try this. No more costly fly sprays. No more inhaling fly spray fumes this summer. No more pesky flies that bite the horses. The equines will love it. Unless, of course, this whole thing is a lot of horse pucky (which is the problem in the first place).