I really do not want to open the ventilation wars which seem to have a 
certain periodicity on this list. For me it is a "to each his own" 
issue. I believe much of the issue depends on the climate in your area. 
You can get by with upper or no ventilation depending on where you are. 
Here in New England, we have high humidity just about all year long, so 
moisture in the hive will be higher than other areas. We also have a 
more constant cold with less warming during the winter. On the other 
hand, I know of colonies that were buried under snow and survived. So I 
would be careful, as in all beekeeping, not to take too much from our 
techniques if you live in an area with shorter and more extreme weather 
cycles and drier air. All beekeeping is local.

I use upper ventilation and a homosote board over the inner cover. The 
board absorbs excess water and the bees use it as a water source 
throughout the winter. If you take off the top cover in winter you will 
see a ring of moisture on the back side of the board. I leave it on all 
year long.

There was a comment on bees in trees and that they did not have upper 
ventilation. Maybe yes and maybe no. I have seen bees in tree cavities 
where the entrance was a slit that ran fairly high up the tree. In any 
case, I think the homosote acts like the top of a tree cavity and 
absorbs moisture in the winter. It is then a close source of water 
during the winter and spring. Many now use it in Maine and it is a 
suggested, by experienced beekeepers, essential piece of bee equipment 
in Maine.

Bill Truesdell
Bath, Maine

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