Arising from the rubble of a medieval quarry, Barnack Hills and Holes is one of Britain’s most important wildlife sites. The site represents half of the surviving limestone grassland in Cambridgeshire and is designated as a Special Area for Conservation to protect the orchid rich grassland.
The limestone was deposited about 150 million years ago in the Jurassic geological period. Quarrying ceased in the 16th century and the pits and spoil heaps were colonised by plants. The area was grazed until the 1940s. Then the whole area became overgrown by trees and scrub.
The site is managed by Natural England and sheep are grazed there in autumn to eat the coarser grasses and encourage the growth of 250 species of wild plants. It is particularly famous for the pasque flowers and 9 varieties of orchid. There are 28 butterfly species including the marbled white.
The reserve is always looking for volunteers – for example patrolling, site management, plant recording, or help with events.On Mondays and Wednesdays volunteers help with habitat restoration or maintenance work such as fencing, scrub clearance, or coppicing.
For further information, contact Christopher Evans (Senior Reserve Manager) on 0797 987 3504, or email Christopher.Evans@naturalengland.org.uk