A Sick Maple Tree
We have a large maple tree in front of our house and it has gradually collected strange markings (?) on its bark. Someone told us it indicated the tree was dying. Can you tell us what it is and if we should either treat the problem or cut the tree down. The tree was small when we moved into the house int 1972.Thank you. A picture is attached.
Montgomery County Maryland
What you have there are some beautiful and harmless lichens.
They are natural and actually can be an indicator good air quality.
They are an interesting life form.
Take a look at this link about them: https://extension.umd.edu/hgic/lichens-trees-and-shrubs
There is nothing you need to do but admire them.
Take a look at this link which covers what a sick tree may look like and help for how to decide whether to remove it: https://extension.umd.edu/learn/how-do-you-decide-when-remove-tree