January 13, 2017 11:40 pm Back Bay Bids Farewell to Elm Tree BOE, short for “Big Old Elm,” died after 135 years towering over Boston’s Back Bay, older than some of the homes in the neighborhood, succumbed to Dutch elm disease. US & World Videos 3:05 100 protesters detained at Northeastern University 2:39 Community mourns police sergeant killed on duty 2:50 Community mourns Billerica police sergeant killed on duty 4:32 Anti-war protester at Northeastern speaks amid arrests: ‘We are peaceful students' 10:42 Multiple people arrested as police clear campus encampments