Green campaigners want to plant an 'M25 of trees' around London to create an animal 'super highway' and improve the well-being of residents.

The London branch of the Campaign to Protect Rural England (CPRE) says fortifying existing woodland in green belt areas surrounding the capital will improve biodiversity and carbon capture as well as create corridors for wildlife.

And the charity is calling on local residents of these outlying London towns to advise them as to where more trees are needed.

CPRE London warned that vast swathes of these areas are currently under threat of losing their green belt status, which would lead to further development of this protected land.

The charity says their proposed Tree Ring Community Forest would help prevent vast urban sprawl akin to that of Los Angeles on the US West Coast - which would result in London being transformed into a concrete jungle stretching across an area equivalent to that between Brighton and Cambridge.

They believe a green ring of trees would play a more powerful role in carbon capture and further help sustain and strengthen biodiversity on the city's limits - as well as improve the well-being of its inhabitants.

A continuous circle of woodland would also help bridge gaps in the green belt; creating green corridors which would help wildlife thrive.

Green belt boroughs such as Ealing in west London and Enfield in north London have recently suggested that substantial areas should lose their green belt designations.

CPRE is looking for help to decide where more trees are needed (image via SWNS)

The council in the west London borough of Hounslow even recently proposed removing protective designations from nearly half (45 per cent) of the borough's green belt and to develop on a fifth (41 per cent) of that land.

CPRE London argues the tree ring will assist the green belt in doing its job to prevent the complete urban sprawl seen in other huge cities across the world.

In Los Angeles, for example, the 'Urban Extent' of the city has increased by 0.4 per cent a year since the year 2000, and 1.2 per cent since 1990, according to figures from the Atlas of Urban Expansion.

According to CPRE London, a similar urban spread in London would soon see the city become a concrete jungle which would cover an area from Cambridge, to the North of London, to Brighton on the south coast.

The charity is calling on locals to help them in their newest green initiative by letting them know which areas already have woodland, and which other areas are in need of some planting.

Anna Taylor, the Director of CPRE London, explained: "There is an urgent need for more tree planting - but this needs to be well-planned with plentiful community input in order to maximise the potential benefits of new woodlands and guard against the loss of other priority habitats or prime agricultural land.

"We need to be creative in thinking about what London's community forest should look like.

"We need to ask ourselves: are there local green spaces near me where trees could be planted that would enhance rather than reduce their amenity value?

"We are interested in the planting of native woodland, but also encouraging the creation of orchards and areas of nut trees, wooded margins for nature-friendly farming, and the establishment of new hedgerows in place of ugly fences."

For the ground mapping of potential woodland creation sites, the charity needs reliable information on existing young woodland in the green belt and more widely across London.

This will reveal where planting can join together with established woodland habitat.

Mature woodland is likely to have already been mapped – but details of younger woodland, planted within the last 20 years, and newly planted saplings need to be collected.

Locals can help by registering possible locations for new woodland creation, or the location of existing young woodlands by filling in a survey at arcgis.com or emailing [email protected] and simply describing the location.

The charity is also asking for donations if mapping is not possible.