Answer: Without knowing what fungus is attacking your tree it's difficult to make suggestions. A wettable sulfur or copper based fungicide is the most organic control I can think of. Some insect damage should be okay for your tree but if you want to control insects as well as diseases you might try a neem oil based product such as Bio Neem instead of the sulfur or copper based fungicides. Neem oil has some residual effect and will control most beetles. Best wishes with your trees!
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