My young apple tree has something occurring to the bark. See photo below. What is it and how do I treat it. Thanks very much! Greg
Certified GKH Gardening Expert
Wow... I have never seen that before, and my research doesn't show much on the subject either! I'm willing to bet that it is something, either, bacteria or fungal in nature. You can try adding wettable sulfur to the area. This can help with the situation but it may not sure it fully.
I would suggest taking a small sample to your local extension and see if that can help you identify the issue.
This article will help you find your local extension: https://www.gardeningknowhow.com/extension-search/