In one of my experimental yards in Western Interior Alaska, I have bees that wintered to -62 F officially and unofficially at -69 F ambient.  The bees are treated with powered sugar and NOZEVIT prior to placing into a hand dug root cellar approximately 5 foot deep.  I put a piece of 2" pvc pipe sticking out for air.  The root cellar is covered with timbers which support sheets of metal and then covered with the dirt that was dug from the hole.  At the entrance of the root cellar there is a piece of plywood about two feet below the surface with straw placed on top of it and then another piece of plywood for the "lid".  I have been placing three hives in the cellar.  When treated with powered sugar and fed NOZEVIT, I have had 100% success.  When testing, I have tried with and without powered sugar and and with and without Nozevit.  Three years is the longest the bees have lasted without powered sugar.  Without NOZEVIT I have a about 50% success - with or with out powered sugar application.  Intestinal integrity is of utmost importance for me.  

The bees go into the cellar usually around the first week of October and do not come out until the last week of April or first week of May, depending on the snow load, temperature, and their activity coming in and out of the pvc pipe. Occasionally it is a traffic jam of bees coming and going up and down the pipe!

The only light comes down the pvc tube.  The area in the cellar is tight - no extra space.  Literally there is only about 1 to 2 foot around the hives.  We see good honey production and need to leave at least 80# of honey on the hives.  I also use Candy Boards as the top cover(400# sugar and 6 gal. boiling hot water heated up on wood stove, mixed in an old wringer washing machine run off a generator).

I use no chemicals unless you call powered sugar and NOZEVIT chemicals.  NOZEVIT is a traditional recipe, all natural herbal from CROATIA.

I return to Northern Croatia on Monday to continue my search for wintering techniques in that area as well as part of the Swiss - Italian - Austrian Alps.

I do not have all the answers but enjoy asking the questions.

Dr. Joe Carson
Alaska Heavenly Honey
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