One of Britain's most famous trees - the mighty 'Robin Hood Oak'

- is being threatened by the current heatwave and needs emergency irrigation.

Around 3,000 litres of water (660 gallons) has been pumped into the ground around the 1,000 year old tree in Sherwood Forest, Notts, which folklore says sheltered Robin Hood and his Merry Men.

The ancient tree - also known as the 'Major Oak' - has trunk with a circumference of around 11 metres (36ft) which is supposed to have helped Robin Hood hide from the Sheriff of Nottingham.

On Facebook, Visit Sherwood Forest, which is run by the RSPB, said: "As the heatwave continues, the legendary Major Oak is feeling the strain — and we're taking action."

"Thanks to the tech we've installed, we've been alerted that the ancient tree needs extra support. We've activated our tree watering system, delivering 3,000 litres of water to its roots."

"This is just one part of our ongoing efforts to care for this iconic natural treasure as it faces even more challenges."

Commenting on the post, Chris Hudson said: "Never seen so few leaves in summer. Water well team."

Others on social media were more negative, however.

Commenter Jennifer Fox accused the RSPB of ‘neglecting' the tree.

In response, Visit Sherwood Forest said: "We absolutely understand the importance of the Major Oak's cultural and natural heritage, and it certainly hasn't been neglected."

"This watering system is just the latest development in a whole range of activity we've undertaken."

"We have been working with leading arborists and soil health specialists for several years, specifically focusing on the health of the Major Oak and possible solutions to the issue of soil compaction around its roots, in particular."

"So, on their advice, the vegetation around the tree is left to grow through its full cycle so its roots fully develop and help to break up the compacted soil, to retain moisture and nutrients and to enhance the biodiversity of its enclosure by attracting pollinating insects and other wildlife."

"We're into the third year of a root restoration programme overseen by one of the UK's leading soil microbiology specialists."

It added: "We're working with the Woodland Trust and a senior academic in arboriculture to use technology to monitor the effect of water uptake in real time."

"We've been trialling soil sensors from across Europe to provide us with data about ground conditions around the tree."

"We regularly bring in an independent tree health consultant to assess the Major Oak and the forest's other ancient oaks and to make recommendations, and skilled arborists are brought in to help us carry out regular health checks."