Quote:
The three standard Langstroth hive body ... or its equivalent in hive space, with adequate and proper organization of food reserves, will preclude starvation as a significant cause of winter loss in the cold northern states or parts of Canada. Sugden et al. (1988) comparing four methods of wintering colonies in Minnesota found that significantly more colonies wintered in three deep hive bodies survived the winter than did colonies wintered in two deep hive bodies.
And that's been my Wyoming experience as well. Although winters here aren't what they used to be, I found that using three hive bodies: