CONSERVATIONISTS are determined to stop a major housing project which threatens to ruin a nature reserve providing wildlife with a crucial haven on the outskirts of Welwyn Garden City.

Quarrying firm Lafarge, which owns agricultual land to the west of the town both north and south of Birchall Lane, has drawn up a proposal for more than 4,200 homes, grouped in six "villages", with development right up to the boundary of The Commons, a nature reserve consisting of grassland, fenland and arable crops grown specially for wildlife near the QEII Hospital.

Green Party campaigner Jill Weston said: "We must be determined to nip this in the bud so it never gets off the ground.

"The Commons has been carefully nurtured for wildlife for many years, and it is very important for people too.

"It is very valuable for Welwyn Garden City, giving people a chance to look at, learn about and enjoy wildlife.

"Under this proposal there will be thousands of people right next to the reserve - that is bound to damage the birds and animals like badgers which live there."

Owned by the borough council, the nature reserve is managed by a group of local volunteers, Commonswood Nature Watch.

Thanks to their dedication, it supports many butterfly species including the rare white-letter hairstreak, water voles and scarce plants such as the spectacular bee orchid.

The arable land is specially planted to encourage declining farmland birds such as grey partridges, skylarks and yellowhammers, while several species of bats are known to use the area.

Reserve warden Peter Oakenfull said: 'We accept the need for housing development locally but brownfield sites must be the first option.

"The Lafarge proposal blatantly fails to acknowledge the reserve by not even showing it on their plan. "If this proposal goes through it would take away the whole point of what we are doing.

"Lafarge are not proposing to build on the resereve itself, but the birds and other wildlife need the surrounding agricultural land as well."

Lafarge has not submitted a planning application but has sent its detailed proposal to the East of England Regional Assembly (EERA).

Campaigners, who fear planning guidance preventing development will be changed by EERA under the pressure of tough long-term government housing targets, have arranged a public meeting to coordinate opposition on February 17, at Howlands Baptist Church.

Neither Lafarge nor Welwyn Hatfield Borough Council has yet responded to the Review's request for comment.