Hello All, I have been looking through a few of the *bibles* of beekeeping and what they say about wintering. I also went back several editions back to the early 1900's. I find that much of the information is copied from edition to edition. Two corrections on wintering need to be made. 1. bees cluster at 57 degrees. Phillips & Demuth (1914) first reported at 57 degrees F.(14C.) the cluster becomes well defined. I have opened many bee hives at 45 and 50 degrees F. and i cannot detect a cluster. At temperatures of 40 degrees or less a well defined cluster as described in the bee books is easy to see. If Phillips & Demuth had said bees start ot cluster then i might halfway agree but most clusters are well defined at 17 degree lower temperature. 2. Main reason for insulating hives. Packing a hive with insulation has the advantage of letting the interior of a hive cool down slowly with a SUDDEN DROP in outside temperature so that all the bees in the hive could get to the cluster before they got so cold they couldn't move. Sudden drops in temps of 30-40 degrees in a short time are not uncommon in winter in our northern states. This reason should at least be talked about. Best wishes, Bob Harrison Odessa,Missouri