Latest action in the neighbors yard

Above is a picture (click for large image) of what our neighbor has been working on for 5-8 hours a day for the last few days. Several months ago he had all the trees in his yard cut down and then the city put in new side walks (they won't do sidewalks as longs as the huge oaks are still there). After the sidewalk was put in he started to dig up the entire yard to about 2 feed deep. As he was digging he picked out every bit of root he could find. When he got to the area on the other side of the sidewalk pictured above he ran into the big roots. He spent several weeks digging around the roots eventually digging a hole so deep that when he was stooped over we couldn't see his head above the sidewalk. I overheard him talking to someone that had stopped to ask him what he is doing (I'm always afraid to ask). He was very upset about the new sidewalk and wanted the city to do it again because they had put it over these roots. I gathered that he was concerned that the roots would rot and cause the sidewalk to collapse. So his solution was to dig a massive hole under the new sidewalk and cut all the roots out with a very small hand saw. All this time we have been hoping that people come to see our house would come in the morning when he is not working.

A few weeks ago he finished filling in the huge hole and then he started working on digging around the stump. He has literally been digging this out with a screwdriver a small shovel and a brush. I am sure he plans to cut this entirely up one small piece at a time. He has already dug up the sweet gum tree stump which was much small but took him at least a week and at least 40 hours of labor. Between these two trees he has spent the better part of three months just digging up roots in his yard. We are very glad he has gotten distracted by this job because he has told me he wanted to put up a fence around the yard. I am sure this will take him an entire summer working full time.