There is a nice study from the Univeristy of Minnesota, summarised in the 
last edition of the Hive and the Honey Bee, in which colonies wintered 
three-high and with no insulation (just black solar-heat absorbing 
sleaves) had significantly higher winter survival and better build-up than 
doubles wintered in Peer 4-packs (insulated walls R-12, lids R-20). Three 
high in black sleaves did markedly better than doubles too.  The study 
spanned three seperate winter and over this span the three-high unwrapped 
had 1.4 times the productivity (survival x (honey production of parents x 
honey production of spring divisions)) of the 4-packs.

I found this finding rather shocking and wondered if it held true on our 
side of the border.  As far as I can tell this has never been formally 
tested on the Canadian prairies.

Adony

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