What I believe to be a sugar maple in part sun in our front lawn by the sidewalk on Bright Passage in Columbia, planted by the builder in 1988, has developed a dark coating that has spread about 8-10' up the main trunk. There are also a number of 1" size patches of green scattered on bark throughout the tree. One side of the tree also has a couple of rows of sapsucker holes. We had the tree pruned by a tree company a couple of years ago in the late fall and it has seemed to be doing okay since then except for the black on the surface that was pointed out to me this fall. A neighbor has advised me that I need to take the tree down and that the sugar maples throughout our neighborhood are developing this problem which will kill the trees. This maple is the first maple in our yard to get fall colors but I think that has always been the case. A neighbor advised me that early color change indicates the tree is dying and should be taken down now. What with the recent removal of all the ash trees in the neighborhood, I hate to remove a live tree unless there are problems associated with not removing it such as spread of a disease to other trees. I'm enclosing photos of the tree, the two sides of the tree showing the black, etc.. Please advise me as to what disease, fungus is impacting the tree and whether there is something I can use to combat the problem.  If whatever it has will result in the tree dying is there an urgent need to take the tree down now rather than wait until it dies naturally.