Answer: Without knowing what kind of fruit tree you are growing it is difficult to guess at any kind of diagnosis. I would suggest you consult with your local Penn State county extension to obtain a specific diagnosis of the problem, and then based on knowing that, decide how to proceed. In many cases fruit problems must be dealt with preventively with dormant season or carefully timed sprays. If this is the case for your trees, they will have the most up to date information on what to use and how/when to use it for best results.
Also, careful sanitation is usually very important for controlling both pest and disease problems on fruit. Always clean up and dispose of fallen fruit and fallen foliage as well as prunings and dispose of them in the trash. This helps limit reinfection from year to year.
In the meantime, you may find the following fruit growing information helpful in planning how to care for your trees.
Good luck with your fruit trees!
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