Well my dog has Fleas, does anyone know of a store close to Phila. that sells "Food Grade Diatomaceous Earth". My plan is to treat my yard, I vacuum twice a day and use a flea comb on the dog who is also treated with Frontline. He seems to be picking up the fleas in the yard. I have a 2yr old son and a pregnant wife so I can't use chemicals it has to be natural.