I’ve just had the manager of Weymouth Parks visit my garden because there is a root breaking up my patio from one of the trees out the back. The guy takes one look at it and said “oh it’s an Elm tree!”
He goes on to explain that Elms aren’t all dead but they all die after about 20 years with Dutch Elm disease. Apparently that’s a combination of Beatle and fungus and the trees can live with one or the other but not both.
So the good news is the council will cut the tree down and Dig the root up in the next month or so.
Well you live and learn.