The lower part of the tree is exhibiting the effects of sun scald.  Bark will crack open as a result of daily freeze thaw cycles during the winter where sunlight shining on that side of the tree warms the tree but then suddenly freezes as soo as the sun sets.  The cracking apparently has extended into the branch collar and beyond.  Here is a link to the U of MN Extension service article on protecting trees against winter damage where you'll learn more about this.

Good-luck!