>>I have bees that wintered to -62 F officially... into a hand dug root cellar approximately 5 foot deep. ... I have been placing three hives in the cellar. ...I have had 100% success. 

I compliment you on your effort!!  Do you know if the temp in the cellar was close to the official -62F?  If yes then I believe the colonies in a ground-level, draft-free shelter such as a barn might overwinter with a similar success. 

>>Without NOZEVIT I have a about 50% success - with or with out powered sugar application.  Intestinal integrity is of utmost importance for me.  

A healthy gut translates to a superior immune system [at least in mammals].  Do you strap the hives and lower them with rope into the cellar?  

Almost 7 months is a very long no-fly period!  What type of bee do you keep and how many bee-covered frames do you find when you bring the hives up?

>>...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!

I assume you see this closer to the 1st week of May.  Do they get some other days for cleansing flights in the winter?  And how do the bees find their way back to their individual hives once inside the cellar - do you have one pvc pipe per hive? 

Waldemar 

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