The dataset consists of pH values from soil samples taken in Roudsea Wood National Nature Reserve in 1961. Soil samples were taken from between 5 and 10cm in depth from transects across the reserve and from under oak trees. pH was measured by the Woodlands Research Section at The Nature Conservancy's Merlewood Research Station, Grange over Sands, Cumbria and the data have been stored and digitised by the Centre for Ecology & Hydrology, Lancaster.