bark following high temperatures in the winter season, resulting in permanent visible damage to bark. What is happening is a process of the living tissue getting wet from fog then freezing which is fine, however on the south side the sun thaws the bark even though the temperature is below freezing, first cloud that passes by creates a quick freeze. This continuous thawing and freezing moves the cell structure too quickly creating damage to the cells.
So how do we stop it? The best way is to use the white cardboard wraps like you see in the nursery. Wrap it loosely making sure the Southwest side is covered and use zip ties to hold it in place for the winter. Then take it off for the Summer when you are certain you will not have anymore freezing temperatures. I do not recommend wrapping the tree. The tape wrap has a tendency to hold moisture and create more problems, especially if you forget to take it off in the spring.