Can anyone please tell me what this is and if I need to treat the tree.
Thank you in advance
Looks like a leaf miner
I agree with your diagnoses, it caused me to go check my young potted Pawpaws that have a leaf problem. Here is a pic of several leaves I removed. Not sure what it may be or best remedy. When I first noticed it I thought it may be sun burn. So I placed them under my persimmon tree canopy. One plant has lost most of its leaves. Looks a bit like Phyllosticta leaf spots? Do you recognize this issue?