We've used diatomaceous earth for over 20 years (parrot cages and around the house for ants,) and in the coop, about 8 years. Monthly, I kick the chickens out and sprinkle it with a parmesan cheese container all over and in the nest boxes.
Our chickens free range under the wild bird feeders with the wild birds, squirrels, chipmunks, etc. and never have gotten mites albeit SLM (scaly leg mites), but these are silkies so prone to get them.
I've used garden/permethrin powder in the parrots cages for the bugs that come from nowhere that are related to a fruit fly. Many use that in their coops when there is a mite outbreak.
I would sprinkle permethrin powder around before putting your bedding back, even do the chickens, then use DE in the coop going forward.
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