Because I am not a chemical engineer, I had to figure out a way to think about this challenge. My horses suffer all summer long from the flies and they can also suffer from the fly spray I put on them. The only commercially available fly sprays that really work for any length of time are petroleum distillate based. These fly sprays make my horses break out in palm sized hives. What to do?
Approaching a problem from any available angle is a hobby of mine. So, I linked turquoise with smell. I think turquoise smells like Vicks Vapor Rub. Guess what? So do flies. As Vicks is petroleum based, I need to cut it with an innocuous medium. Flies don't like vinegar either. Vinegar is a pale turquoise smell, add it to Vicks [put the tub in the microwave and melt it or buy the liquid, more expensive form if you don't want your kitchen smelling like a sick child] and you have a pretty good fly spray. To make it stick better, add a little original formula Dawn dish washing liquid, which is also, you got it: turquoise.
Yes, it smells awful at first. But when the flies buzz away, turquoise starts to smell pretty sweet.
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