Enfield Council workers discovered the tree, which measured 6.1 metres around its trunk, surrounded by its severed branches in Whitewebbs Park, Enfield, last week.
The incident, which took place on April 3, has been reported to the Metropolitan Police and the council has put an emergency preservation order in place on the base of the stump.
The tree was thought to be in the top 100 of London’s oak trees in terms of its size.
Ed Allnut, secretary of the Guardians of Whitewebbs group said people wanted justice for the old oak.
“The tree belonged to Enfield and to our national heritage. I am personally devastated,” he said.
“We want answers, and we want guarantees the other trees here are being protected properly.”
The Woodland Trust, which has been advocating for legal protections for the country’s oldest and most important trees, called the incident “devastating”.
Adam Cormack, the charity’s head of campaigning, said: “We don’t know yet who did this or why and would urge anyone with information to come forward and report it to the police.
“This depressing crime is a reminder to all of us that not every ancient tree is in a safe place.
“It is very unusual to see the felling of an oak tree of this size and age.
“Legally protected status for trees like the Whitewebbs Oak is long overdue.
“This issue has widespread public support and is an open goal for the government to act upon.”
Enfield Council leader Cllr Ergin Erbil said: “The council was not informed of this incident until last week. Our teams immediately carried out a full site inspection to assess the damage after receiving reports of the damage done to the tree.
“We are treating the matter as criminal damage and have reported it to the police. We’ve now placed a legal protection (Tree Preservation Order) on the tree and are looking at ways to help it grow back.”
The Woodland Trust’s Living Legends petition was handed to Downing Street with 100,000 signatures in November and the Heritage Trees Private Members Bill, which was introduced in the House of Lords by Baroness Young in 2023.
The legislation proposes the introduction of a list of nationally important heritage trees and a preservation order that could be used to promote the protection of ancient and important trees.
The Tree Council and Forest Research published a report on Monday, calling for a “robust and effective system” of protections as part of a wider action plan to protect England’s most important trees in the wake of the Sycamore Gap tree felling in September 2023.
The trial of the two men accused of felling the Sycamore Gap tree is due to take place later this month in Newcastle Crown Court.
