On Monday, July 14, 2014 9:56:04 AM UTC-4, amdx wrote:
On 7/13/2014 6:58 PM, SteveB wrote:

look for copper pennies in water in plastic bag fly repellent

Where am I supposed to be looking?

Have you seen any serious studies of this method?

"Yes they do work. I don't really know why but it does help. We had a bad fly problem on our side patio. To the point you couldn't stay out there a couple of mintes without being swarmed with flies. I had seen the water bags used at a local cafe/bar and was skeptical about it but thought it was worth a try. I hung 3 1-gallon ziplock bags of water from the rafters along the outside edge of the patio and by the next day there were very few flies. Now out in the yard (where they were also bad) they are still there, but within 10 foot or so of the patio, there are hardly any.
I have noticed in the late afternoon (patio is on west side of house) when there is a slight breeze causing the bags to twist and sway, the sun hitting them makes it look like we have a slow moving disco ball going. Maybe its the water acting like a prism, causing moving spots and flashes that scares the flies away. Maybe a wind chime made of mirrors would do the same trick?
Also, I have never heard or seen the thing of putting pennies in the bag. Not sure what that would do, other than, I did put a marble sized rock in the corner of the bag to have something to wrap and tie the string around...maybe the first person to do this used pennies and got something started?? "
- TX Cowboy

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