I recently had some maple tree trimmed and the person in charge told me that he thought one of the maple trees has Verticillian Wilt. From what he said and information from the internet it appears that if the tree is infected it is usually fatal as well as contagious. How can I be sure that the tree has this disease and is there a way of "curing" the tree? I see no obvious signs of a problem by looking at the leaves.
The MSU Plant & Pest Diagnostics Lab (https://pestid.msu.edu/) can confirm whether or not the tree has verticillium wilt (there is a fee). Be sure to follow the instruction for preparing a sample for the disease. There really isn't a "cure" as such but you can manage the disease by keeping it healthy. Check out the following links:
I hope this is helpful,