Hi Everyone,
Lloyd Spear already mentioned the research that has shown that the
bees don't heat the hive outside the cluster.  Quite a few years ago
now Dr. Haydak wintered some colonies of honey bees outside on the
University of MN St Paul campus with only screen on the top and bottom
of the colonies.  The bees did fine.  This was done to show that the
bees don't require additional heat if you have a good strong colony
with plenty of stores even outside here where we have winter
temperatures that usually get into the -20 to -30 degree range.

Removal of moisture to prevent dripping on the cluster, keeping mice
out of the hive, and wind protection are important for wintering.
More recent research has shown that more insulation is of benefit to
colonies infested with tracheal mites but good healthy disease and
mite free colonies don't need that extra protection.  Added heat or
insulation can reduce winter feed consumption but is usually not
actually needed in most parts of the US.

blane


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Blane White
MN Dept of Agriculture
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