SAFEGUARDING HEATHLAND HABITAT OF THE SILVER-STUDDED BLUE BUTTERFLY
CONSERVING AND RESTORING PREES HEATH COMMON RESERVE
CREATION OF NEW LOWLAND HEATH HABITAT AT PREES HEATH COMMON, NORTH SHROPSHIRE
Commencing in 2006, Butterfly Conservation started work to create a new large
area (>20 hectares) of lowland heathland and acid grassland on existing arable
land at Prees Heath Common, Whitchurch, Shropshire. The existing small and
fragmented areas of heathland on Prees Heath Common supports the only remaining
colony of the Silver-Studded Blue butterfly (Plebeius argus ) in the English
Midlands. A much greater area of heathland covered the site one hundred years
ago and thus the heathland heritage provides a historical precedent for
heathland creation. Silver-Studded Blue butterfly was once (60-80 years ago)
much more common in Lancashire, Cheshire and Shropshire but loss of habitat was
a significant factor in the decline of this species.
Ecological Restoration Consultants was commissioned by Butterfly Conservation to provide guidance on how the site could be successfully restored to the target heathland vegetation which is a priority BAP habitat for Shropshire. To create new lowland heathland on fertile arable farmland presents a major challenge, but expertise provided by Ecological Restoration Consultants crated a potential solution.
An initial survey of Prees Heath Common involved digging a series of trial soil pits at different locations and soil samples were analysed for chemical and physical properties. The results demonstrate that successful restoration to heathland is feasible due to the presence of underlying nutrient deficient sands and gravels. Having ascertained that there were no archaeological constraints, Phase I commenced in March 2007 when the soil profile was inverted to a depth of 90cm using a Bovlund 64D plough. 6.35ha was ploughed and the exposed sand subsoil was spread with sulphur pellets which were harrowed in. The initial pH of the subsoil was 7.1 – 7.7 but by September 2007 this had dropped to 5.3 -6.2 and by June 2008 pH was down to 4.0 – 4.7. The application of sulphur had produced the intended result.
Heather brash was harvested at Cannock Chase (the nearest suitable donor site) transported to Prees Heath in late November 2007 and spread on the sulphur treated area at a rate of 15.5 tonnes per hectare. This provided 4900 seed capsules per m2 (approximately 37,000 seeds per m2). In July 2008 numerous heather seedlings have emerged. Restoration will continue with Phase II during autumn 2008 when a further deep ploughed area of approximately 6.5 hectares will receive sulphur and harvested heather brash. The project will continue for at least 10 years.
Click here to view a
presentation about Prees Heath Common
(pdf - opens in new window)