I'd like to plea for more trees in soccer-stadiums: 1) They add an element of fun to the game; 2) They don't get aggressive easily; 3) Everyone supports green.
Sebastian Errazuriz: A 10-meter high, real magnoilia tree planted in the center of Chile's National Stadium where dictator Pinochet tortured political prisoners 30 years ago. During a whole week [somewhere in 2006, red.] the de-contextualized stadium was open to the public as a park. A cathartic soccer match played before 15.000 people, with the tree in the middle was the closure of the piece.