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Yes, you're quite right - it's 100 nights below freezing, not 100 nights below zero. I could pretend that I meant zero Celsius, but that would be an alternative fact.
I think what you are referring to is the chilling requirement to break bud dormancy. Different northern tree species have different cold temperature requirements necessary to break down growth inhibition compounds to allow the buds to become active. Sap flow in maple is a very different biophysical process. It will happen any time the leaves are off and the temperatures go from below to above freezing.