I don't know if those patches would work around here cause we got way more than 7 deer flies. For about 3 weeks in July we have so many deer fly that once I grabbed the kids butterfly net and swooped it around my head while going for the mail. When I get done I've got a ball of deer flies in the net about the size of a baseball. I smashed them and dumped them in the pond - fish food! My kids invented something better than the patch. We all wear hats during deer fly season because that at least keeps them off your head. When my kids were younger they always wore straw hats. One day I saw my kid walking down the driveway with a young chicken sitting in the hollow spot on top her staw hat and it was eating deer flies as fast as it could scoop them up. She named that chicken flycatcher.
