I have about 10' Glowing Embers Japanese mapple that I planted last year, and I just noticed that the trunk seems to be damaged on one side. I can't tell if this is recent or it happened last year. The tree is in shade in morning, and in full sun in afternoon, and this is the side directly towards sun. Also, in the bottom of the picture, you can see that even where bark is not gone, it is still discolored, which got me thinking that this might be due to sun exposure rather than some animal.

Is this possible, or does someone have a better explanation? I'm in central Texas.