Why is there a tree in the middle of the pitch?

(From Guardian Unlimited)

"I seem to remember a photo from about 15 years ago, possibly in FourFourTwo, of a Brazilian lower league team with a tree in the middle of their pitch," writes Ian Boutle. "Can this be confirmed? And are there any other arboreal oddities of note in the wide world of association football?"

Rest assured, Ian, you're not going doolally. In fact, there are a few examples of our leafy friends finding their way on to football pitches. The Brazilian tree on the pitch can be found in S'o Paulo.

"Indeed it exists," writes Claudio Kristeller, who handily sends in this link (scroll down). "However, this pitch is not used for any kind of official championship, it is for leisure only."

There was also a tree planted in the middle of the national stadium in Santiago in 2006 by the Chilean artist Sebastian Errazuriz. The project was "a 10 metre high, real magnolia tree planted in the centre of Chile's National stadium where the dictator Pinochet tortured political prisoners 30 years ago", notes the artist's website. "During a whole week the decontextualised 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."

Not quite on the pitch, but occasionally interfering with play was the famous 'late tree' at St Albans' ground. "Up until 1998 the …