Why is my Pink Dogwood losing its leaves?

My Pink Dogwood tree bloomed in the Spring, but now the leaves are turning brown and falling off. Also there is green scaley mold on the trunk.It is about 4 years old.

Answers:
Check out some of these University sources:

My first guess was Anthracnose, but leaves turning brown and falling off is NOT one of the more typical symptoms. It is best to consult a local horticulturist, or extension agent.

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