DE = Diatomaceous Earth. Fossilized diatom (miniscule ocean dwellers) shell. Two grades: One for swimming pool filter--DO NOT USE FOR ANIMALS!!! The one you want is FOOD GRADE. It MUST be labeled that way! Some people swear that it prevents or even treats mites. I've had no luck with...
I wonder if a cranberry rake attached to a handle would work well? Don't know where you find a cranberry rake outside of the East coast. Might be expensive.