Limestone pavements

Limestone pavements are unique habitats found only where limestone rocks occur. Created by the action of glaciers during the ice age, aided by the activity of primitive farmers, the soil has been stripped away, leaving bare rock exposed to the elements. The little soil that remains is either a thin layer on the bedrock or is hidden in the fissures - known as grikes - between the blocks of limestone. The plants that can survive here are those adapted to dry conditions and thin, calcareous soils of the open areas, plus those that like the more humid and shady conditions in the fissures. Classic examples can be found in northern England in the Yorkshire Dales.