Re: Hive entrance size.
My hives in summer have an entrance 3/4 of an inch high and open from one end to the other of the front of the box. This is to allow suffeicient ventilation when they are evaporating moisture from summer nectar flow, plus bees getting in and out. I purchased some commercially made bottom boards that had the opening all the way across but are only 3/8ths inch high and the bees noticeably struggle with ventilation on the busy days. So for me anyway, 3/4 inch high is right.
Winter here is mild so entrance reducers are 4 inches across. But where winters are very cold a much smaller entrance may work, that would be a judgement call based on the beekeepers observations in his climate.
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