USING limestone in rockeries could be robbing Lancashire on one of its rarest natural landscape features, Lancaster gardeners have been warned.

A new report, produced for the Countryside Agency say's that Britain's few remaining areas of limestone pavement -- half of which is in Lancashire and Cumbria -- could be destroyed by the fad. It provides a unique environment for several plant species. Richard Lloyd, of the limestone pavement biodiversity action group, said: "We would like to see further protection of water-worn limestone in the UK and Ireland, and people thinking twice about using water-worn limestone for rockeries when alternatives such as deep-quarried limestone, granite or artificial stone are readily available."