|Looks ghostly...or ghastly depending on your expectations.
It is a thing.
Some species of trees; peaches, cherries, apricots, Carpathian walnuts for example are vulnerable to sun scald. The sun heats up the trunk on the southwest side on sunny days. The bark is most quickly warmed just above the snow line. The bark breaks dormancy. Night comes. Temperatures plunge. Ice crystals form and puncture tender cell walls. Tissue dies.
|Support on left. Tree on right. Sun scald damage on tree in center of frame. Bark died and you see a rectangular "window" of bare wood.
|Another sun scald injury on a different tree.
The preferred solution is to paint the trunks and major limbs with diluted, white, latex "ceiling" paint. Interior paint has the fewest amendments that might be toxic to trees. It is also exceptionally inexpensive at $10 a gallon.
I diluted the paint about two-parts water to one-part paint. I put it in my garden sprayer and dialed the nozzle to spray just slightly wider than a narrow stream.