I bought mine online, I can’t remember where I got it from, I just went with the one that had the best price. It’s sort of expensive, but a little goes a long way and I never really had mites, but I was afraid my chickens would get them so I sprayed the inside of there coop and run with it a...
I would bag up all that hay and get rid of it! Then I would spray. I have only used elector PSP, but if you have permethrin, I would use that and after it dries sprinkle the DE.