Question
Hi Jim!

I have maple trees on a front lawn. They are old, probably 50-75 years old, maybe more. One of the trees is showing 3 symptoms:

1- moss is covering some of the bark. This is also visible on trees of my neighbors.
2- some bark has fallen off  the trunk
3- mushrooms appear on the bark, here and there.

I live in S.E. Pennsylvania

Your comments and advice, please?

Thank you

Chris

Answer
You did not say which maple you had --silver maple has a life exopectancy in a yard of about 20 year where sugar maple lives 75-100 years. I would say your tree are reaching the later stages of their life expectancy. Sounds like rot fungi has hollowed out the trees. (the mushrooms). Bark does fall off maples as they grow. I would recommend that you look at the foliage and if it is green and full then the tree is doing ok. The rot fungi will not kill the tree but may make it weak and high winds could break it. If you still have concerns I would call the local office of the Penn. State Forestry agency and ask one of their Foresters to come out and take a look and advice you on whether the trees need to be replaced. An on the ground look is better than I can do without seeing the tree. Their phone number should be in your local phone book.