I have a flowering crabapple in my yard whose bark has several large areas where it cracks and curls away from the wood underneath:
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I don't know what variety it is (the previous owners planted it), but it's a flowering crabapple with fragrant pink flowers and inedible 2" kidney-shaped fruit. I live in Portland, Oregon, USA which is USDA zone 8a.
My questions:
- What is causing this damage and how can I treat it?
- Should I be worried about it spreading to my real apple tree which is approximately 20' away?