Re: Opening Hive
You have mold because there was too much moisture / humidity in the hive over the winter. You will continue to have this problem until you find a way to vent that humidity. Wet bees are more at risk of dying than cold bees.
If you feel that a simple top vent is not what you want, some people use a "quilt box" style with leaves or wood shavings acting as a partial barrier.
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