I wanted to build off this question if I could. What do we do with deep freezes ahead of the hibernation period? In Denver we are hitting single digits tonight and tomorrow and some deciduous trees haven't lost leaves, so I think it is safe to say they are still building sugars and preparing. But to clarify - I'm thinking temperatures so low that there is a risk of freezing even if it were winter. I might be way off since I'm inexperienced...Maybe they are totally fine in the pre-winter drops. Should trees be brought in from the external, unheated storage to prevent freeze or should they be subject to fluctuating temps? Tree examples would be Acers, Junipers, and Cedars.