Specialist tree surgeons are installing slow release chemicals to encourage the roots to grow. They will also use a crane to remove a number of the heavier limbs to prevent the tree from falling or blowing over.
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Highs on Thursday of 18C.
Barnet Council ran the school, which was an institution for young people with learning difficulties.
Bowers pleaded not guilty of assaulting his ex-fiancee Sophia Cahill in Croydon in January.