A North Carolina man suspected in several area bank robberies has admitted in court that he was responsible for the robberies. Will Smitherman yesterday pleaded guilty to robbing a SunTrust Bank in Forest last February. According to investigators, Smitherman also robbed banks in Galax and Roanoke early last year. Smitherman wore a hat and "mullet" wig during the robbery, leading prosecutors to give him the nickname "Joe Dirt" because he resembled a movie character with that name.