The leaf of a cherry tree affected by Shothole disease.
The name for this disorder is self-explanatory. It can be caused by a number of fungi and bacteria, but the usual culprit is the fungus Clastosporium carpophilum. The affected area of the leaf dies and turns brown, eventually shrinks away from the surrounding tissue and falls out. The size of the resulting hole can vary, depending on the severity of the infection.
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