Possibly frost cracking that has since healed or other damage from planting time. How long has the tree been in the ground?

Bill, it has been in the ground for 3 or 4 years. We did have a particularly cold winter this time around.

Slight frost cracking, not a big deal.

Frost cracks are often found on trees that are out in the open where sun shines directly on the bark. Cracks are first initiated on a winter’s day when sunlight warms the bark and inner wood on the south or west side of the tree, especially on young trees with thin bark. As the sun sets or is hidden by clouds, the temperatures drop quickly causing shrinkage in the bark while the inner wood takes longer to contract. This unequal shrinkage or contraction between the bark and the inner wood causes the bark to split and along with it the wood directly below the bark. Scientists believe it actually results from water moving out of cells and freezing during sudden drops in temperature. The wood closest to the surface shrinks as water is lost quickly while the inner wood is not affected. The sudden change creates pressure between these two zones resulting in the wood cracking.