Ever Seen Bags of Water Hang From a Porch? Here's What That Means

Plastic bags half-filled with water and containing a few pennies might seem like odd outdoor decor if you've never encountered them before. Yet you can see these contraptions all over the American South, from barbecue restaurants to your neighbor's back porch. But what are they for? Read on to find out.

A useful purpose

Believe it or not, these bags are an insect repellent. If you live in the South, you'll know that summer means bugs. Mosquitos, ants, June bugs, and most annoyingly, flies! Flies reproduce in the warmer months, so Summer is prime fly time. If these nasty critters get inside your home they will gravitate toward any food, even if it's currently being eaten by you! Flies carry loads of bacteria and can spread dangerous germs including salmonella, e.coli and even cholera, so you definitely want to get rid of them.

It's not entirely certain why the bags work, the Tennessee Farm Bureau speculates it's because the pennies appear magnified in the water, which irritates the flies, who have large, sensitive eyes.

"The fly bases his movement by light and the refracted light coming through the water in the plastic bag confuses the fly causing him to move on to a place that is easier on the eyes," the TFB website states.

What else can be done?

To make your own fly repellent, simply get a gallon-sized zip-loc bag, fill it half to 3/4 with clean water, and drop 3 or 4 pennies in the bottom of the bag. Once the bag is firmly sealed, it can be hung from or nailed to an eave near a doorway to keep the nasty critters from entering your home. In addition, they can be hung over picnic tables or other outdoor seating to keep flies away from your patio.

Other ways to combat flies are to clean pet waste from your yard, since flies are known to breed in feces, and keep a tight-fitting lid on any outside garbage cans, which are another favorite breeding spot for flies.

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