@cassy, here in the US mites are resistant to carbaryl, and in some parts of the country they are resistant to permethrin. What chemicals are available in Canada?
Welcome to BYC! The best thing to try first is permethrin. Go to Tractor Supply, or any feed store and buy a 10% permethrin spray concentrate that is labeled for on poultry. A small bottle should cost less than $10 and will make many gallons.
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