> 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.

While this is true, this does not necessarily indicate that the bees will be in
as good condition in spring or that the survival rate per 100 hives will be as
high compared to bees that are sheltered properly and/or wrapped according to
the needs of a particular district.  And bees may not heat the area outside the
cluster much under most conditions, but the cluster *size* will be *much
smaller* in a cooler hive, meaning less food is in the cluster and perhaps less
brood can be protected.  This can mean colony death in some situations.

I realise that I'm repeating myself, since this has been heavily discussed in
the past, but to recap, we have found that some years bees need protection, some
they don't.  Who knows in advance what year will bring two weeks of minus forty
weather with strong winds in February when the bees are weakening from being
confined, and also vulnerable due to increasing brood rearing?  Who can tell for
sure when the bees are a bit weakened by disease, parasites, or a bad previous
summer?

It is also imortant to understand that limited tests with one strain of bee in
one locale will not prove anything for all types.  Sure, livestock can often
survive without shelter and care, but most good operators try to provide more
than the minimum requirements.

Farrar (as I recall) many years ago did studies using electic heat tapes and
concluded that they were a benefit.

Artificial heat CAN be a bonus when applied properly and with careful timing.

 > Added heat or
 > insulation can reduce winter feed consumption but is usually not
 > actually needed in most parts of the US.

True, but where it is needed, it is needed.

Sorry to be so brief, but time is short and much more is in the logs under
wintering , wraps, survival, etc.

allen
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