Answer: Unfortunately, based on your description, I am not certain what is affecting your trees. However, there are a number of possible problems that could be affecting them such as budworms (larvae of a moth), a fungal infection, and/or damage due to the oscillating temperatures last winter and spring. Dieback is never a good sign. I would strongly suggest you consult with your local Penn State county extension to obtain a specific diagnosis of the problem(s) and based on knowing that, decide how to proceed. If a chemical control is recommended, they will have the most up to date information on what to use and how/when is best to apply it. I'm sorry I can't be more specific long distance. Good luck with your trees.
Q&A Library Searching Tips