Mustard key to worm count plans

They might be slimy, slithery and wriggly - but according to Darwin, worms are one of the most important creatures on earth.

And with their habitats increasingly under threat, volunteers are being asked to help with an earthworm 'census'.

The £500,000 project will see amateur scientists pouring mustard - a mild irritant to worms - on their flowerbeds. They can then identify any disgruntled (but otherwise unharmed) specimens which surface.

Census: Volunteers are being asked to chart the earthworms in their gardens as part of a £500,000 research project

The collated results will be used to shed light on one of Britain's most common, but also most poorly understood, creatures.

Organisers also hope to identify rare species which could be on the brink of extinction.

David Jones, of the Natural History Museum, said that surprisingly little research has been done on earthworms since Darwin wrote in the 19th century: 'Worms have played a more important part in the history of the world than most persons would at first suppose.'

Mr Jones added: 'Darwin did a lot of work on earthworms at his home in Kent, but since then the research has been sporadic.

Slimy and slithery: Darwin said worms are one of the most important creatures on earth

'We don't fully understand which earthworms live where - and which particular species like which types of soil.'

Although there are dozens of ways to encourage worms to the surface, including imitating rainfall or rubbing a metal pole in the ground to simulate the burrowing of a mole, rigorous research has shown that dousing soil in mustard is the most effective technique.