Thanks buzzbee. Excellent article.
A word of caution to those who would use OA in early winter in a bloodless period. Yes it should work well to control the mite population, BUT remember, you need to have healthy bees to get the colony through winter. This means you have to have the mite population down enough by July/August for the colony to be able to raise healthy bees for winter. Unless you virtually wiped out all mites the previous winter, you will have to many mites by late summer for the raising of healthy brood. This means you may need to use another option like Hoppguard in July, practice dron comb removal, etc. to knock back the mite population enough to get by till you knock em dead with oa come winter.