The bees are flying today (And bringing pollen in! It's mid February in northern Utah!), so I took the opportunity to lift the lid of both my hives and peek inside.

I was dismayed to find that the IC of one hive had a lot of mildew on it, damp and warped. Obviously, ventilation is an issue. To make matters worse, at the front end of the hive, the moisture had dripped down onto the ends of the top bars of the frames, and they have some mildew on them.

The box on the top (the one with the mildew on the frames) is a honey super. Obviously, this is a box I want to use and harvest from in the future. Hopefully the mildew is just on the ends of the top bars, but assuming the worst, how should I clean the frames off before I can extract from them?