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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The twins cubs, which were born in June, have been named Bert and Ernie after characters from Sesame Street.
The two victims died from their injuries in hospital after the explosion in Hertfordshire.
Investigations are continuing into the cause of the crash in chigwell which killed both people on board.