At one time, many Montana beekeepers packed their colonies in straw.
Hardly anyone does anymore.  Besides the inconvience, the straw often
became a source of a problem.  Unless care was taken to make everything
water tight, during a mid-winter thaw (like we usually get in January)
the snow on top of and around the hive melts.
 
The straw acts like a wick and gets soaked.  Then, the temperature plummets
and the whole thing becomes a block of ice.  During the next thaw, the
bees are encased in a dripping, soggy mass.
 
Now days, the less is more approach is taken.  Some wrap, others don't.
Some use the waxed cardboard boxes.  Many wrap in roofing felt - no
straw.  A few put a bit of styrofoam on top of the cover under the felt -
I have no idea whether this really helps or not.
 
Inner covers are used to provide an escape route (hopefully above the
snow line on warm days).  Many do not use them during the summer.  I have
never seen much evidence that they do or do not make a difference.  One
hears the arguements, but no hard data.
 
Jerry Bromenshenk
The University of Montana
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