The workers of the Enfield Council discovered the tree, which measured 6.1 meters around its trunk, surrounded by its branches cut in Whitewebbs Park, Enfield, last week.
The incident, which took place on April 3, has been informed to the Metropolitan Police and the Council has established an emergency preservation order at the Basque base.
It was thought that the tree was in the top 100 of the London oaks in terms of its size.
Ed Allnut, secretary of the guardians of the Whitewebbs group, said people wanted justice for Old Oak.
“The tree belonged to Enfield and our national heritage. I am personally devastated,” he said.
“We want answers, and we want guarantees that the other trees here are being protected correctly.”
Woodland Trust, who has advocated legal protections for the oldest and most important trees in the country, called the “devastating” incident.
Adam Cormack, the campaign manager of the charity, said: “We still do not know who did this or why and urged anyone with information to be presented and report to the police.
“This crime of depression is a reminder for all of us that not all old trees are in a safe place.
“It is very unusual to see the felling of an oak of this size and age.
“The legally protected state for trees such as Whitewebbs oak is very late.
“This problem has broad public support and is an open objective for the government to act.”
The leader of the Enfield Council, Cllr Erbil, said: “The Council was not informed of this incident until last week. Our teams immediately carried out a complete inspection of the site to assess the damage after receiving the reports of the damage caused to the tree.
“We are agreeing on the matter as a criminal damage and we have informed the police. We have now placed legal protection (order of tree preservation) in the tree and we are looking for ways to help you grow again.”
The Legends Living of Woodland Trust’s request was delivered to Downing Street with 100,000 signatures in November and the bill of private members of heritage trees, which was presented at the House of Lores by the young baroness in 2023.
The legislation proposes the introduction of a list of important national trees and an order of preservation that could be used to promote the protection of old and important trees.
The Tree Council and Forest Research published a report on Monday, asking for a “robust and effective” protection system as part of a broader action plan to protect the most important trees in England following the felling of sicomorous gaps trees in September 2023.
The trial of the two men accused of cutting down the Gap Sycamore tree is due at the end of this month in Newcastle Crown Court.
