I'd be using a product called "Worry Free" from Wal-Mart, garden/yard section. Comes as powder, concentrate, or ready to use spray. It's Pyrethrins, in other words natural (chrysanthemum). The concentrate has also PBO in it. I'd try rubbing fawn down with powder. This stuff can be applied on vegetables up until harvest. Used it on 5 week old, sick kittens that I found in my driveway several weeks ago and it actually worked on fleas without getting the little ones sicker.