Chances are that this one tree could have been on the border of two mammalian territories, and every beast stopped by to pee on said tree, about June or so during the mating season....thus the stupid tree grew, got warmed up or hot or whatever....and these yo-yo scientists make a big deal out of an individual.
Real scientists would never make any assumption on an individual.
BA
I think Dr. Mann had cross-sections cut from a number of trees that'd washed down to the bottom of the hill.
This particular paper indicates that it didn't matter how he cherry picked his sub-samples since he had total liberty to interpret the tree rings any way he wished ~ with no one having a modern tree grown at that site to compare it's growth behavior to thermometers.