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The decision to move a grassland, rather than protecting it from a development threat and managing it in situ, has always been a controversial one. A case study by English Nature of the translocation of a grassland in Devon provides an overview of a project which failed to achieve the objective of safeguarding the original grassland community.
The case study is a compilation of the evidence presented at a Public Inquiry into a proposal to tip ball-clay waste onto a SSSI at Brocks Farm, Devon (subsequently refused by the Secretary of State, see British Wildlife 10: 215), together with some supplementary information. It includes sections on the method, management and monitoring of the translocation of a species-rich lowland meadow in 1988 in the same locality. This report on a translocation project is unusual because of the long-term monitoring, the presence of a control site and detailed statistical analysis.
The translocation arose as the result of the granting of planning permission in 1986 which included the tipping of waste onto a species-rich lowland grassland (NVC community type MG5) containing a substantial Green-winged Orchid Orchis morio population. In autumn 1988, translocation was carried out using two methods: by moving turves and by spreading rotovated vegetation and topsoil (littering). An adjacent field with the same vegetation community was managed in situ and acted as a control. All areas received the same management, by cutting and latterly cutting with aftermath-grazing by sheep. Vegetation-monitoring took place before translocation and annually thereafter.
The conclusions were that the most important difference between areas was the effect of the translocation and that there was a trend common to all areas associated with grazing Ð all areas had been unmanaged for a period prior to translocation. In comparison with the control, the translocation by littering led to immediate changes in the community.
This was followed by partial recovery, but even after eight years substantial differences existed, including the presence of ruderal species. The translocated turves appeared to change very little initially, but in recent years floristic differences from the control indicate that long-term damage has occurred. The NVC community of the turved area is now more like MG6, the widespread community of improved permanent pastures on free-draining soils. The report contains the warning that a short-term monitoring programme might have judged the turf translocation a success.
The report, published by English Nature, includes information wider than that of the method, management and monitoring of the translocation, covering matters of planning policy. It is available free from the English Nature Enquiry Service, tel. 01733 455101. It is titled Grassland habitat translocation, the case of Brocks Farm, Devon, reference English Nature Research Report number 304.
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