Quote Originally Posted by Dark Bee View Post
Open mesh floors with the tray removed are the invention of the devil.
Hmmm...I think this is an area where a multitude of beekeeping opinions is at work. No definitive answer either. My bees have done very well on open OMfs since I started beekeeping 9 years ago. I leave them open through the winter, usually with Kingspan on top of the crownboard. And all is dry and cosy within. My hives are on 12 inch high stands with sides about 3 inches deep so are protected from direct wind blowing up through the floor.

Where I try to overwinter bees in my solid floored nucs they're invariably damp and unpleasant come Spring time. I tried and succeeded to overwinter a couple of Paynes polynucs with OMFs and the bees did very well in them - dry, warm and cosy even here in the frozen north!