I am seeing a lot of Band Canker (Botryosphaeria spp.). Not many years ago it was uncommon. Now it seems I can find it in any young orchard. The moisture held by tree protectors (cartons) may contribute to the ability of the fungus to invade. We removed the cartons in this orchard but the gum caused by the canker made it difficult to remove the carton from this tree.  You can see the white remnants of the carton that stuck to the gum balls. I have always been an advocate of removing the cartons as soon as possible because they shelter scale insects and overwintering Peach Twig Borer.