Q.crepe myrtle bark
My 12 year crepe myrtle has something eating the bark, with huge gashes extending up the tree. Seems otherwise healthy. What could it be? It has seemed fine. I just noticed these huge lengthy gashes on several of the big trunk areas. Must have been there for a while. Bark just pulls away and looks like what might have been webs inside. No bugs visible now. Is there a spray for this? Would hate to lose my 12 yr. old tree.
It sounds like you are describing natural shedding of the bark.
I would although inspect the tree carefully for insects or bugs. Aphids will leave a webbing substance.
Here are a few links for you.
https://www.gardeningknowhow.com/ornamental/trees/crepe-myrtle/bark-shedding-crepe-myrtle.htm
https://www.gardeningknowhow.com/ornamental/trees/crepe-myrtle/crepe-myrtle-tree-problems.htm