Thanks for the good image sent offline. This is the dried exoskeleton of a cicada having emerged from a 13 or 17 year cycle spent in the soil. Once the insect emerges, the skin will split and the adult cicada with wings will take flight, mate and lay eggs. This is not likely causing any problems for your trees.
It has been a challenging year for many plants. Parts of the state received excessive spring rains, others not. Hot dry summer weather has also stressed plants around the state. Many plants have foliage disease problems, but are not life threatening usually. Stressed plants over several years are good targets for boring insects, which can damage or kill a plant. Before taking strong measures like removing a tree, be sure of what is the cause, can it be treated, can you reduce the stress, etc. If your concern is strong, consider consulting with a certified arborist and get two or three opinions as to what is going on.
Cheers, Richard
