In the course of thinking about screen bottom boards, Nathan asks "And if
screen bottom boards ONLY are used, would this make it more
difficult for the bees to keep warm in an upstate NY winter?"

I think the answer to this question is a resounding "NO", as at least one
commercial beekeeper has been using nothing else for over 30 years!  (And he
does not migrate.)  I have just 2 years experience, but the same results.

The more important question is whether we should keep using screens alone.
While the Canadian researchers are well respected, their data and methods
have not been peer-reviewed so I am going to continue to use screens alone
until there is more information.  I am also going to keep my solid
boards...which I was planning on disposing of.  Next year may be another
matter...

Lloyd
Lloyd Spear, Owner of Ross Rounds, manufacturer of comb honey equipment
for beekeepers and Sundance pollen traps.
http://www.rossrounds.com
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