Nash's Field grassland experiment Silwood Park, UK

Nash's Field is one of the field experiments of Imperial College London, Silwood Park campus and is part of The Ecological Continuity Trust (ECT). The experiment is a long-term study that aims to understand the degree to which nutrients, soil acidity and herbivory affect grassland ecology. It is a five-factor factorial experiment replicated in two blocks of plots using a split-plot design in a neutral grassland (MG5 Cynosurus cristatus/Centaurea debeauxii, under the UK National Vegetation Classification system). Overall, the experiment contains 8 invertebrate exclusion plots (± insects and ± molluscs, 22 x 44 m), 16 vertebrate exclusion plots (± rabbits, 22 x 22 m), 32 soil acidity plots (high vs low pH, 8 x 18 m), 96 plant competition plots (± grasses, ± herbs, 6 x 8 m) and 1,152 fertilization plots (12 combinations of N, P, K and Mg, 2 x 2 m). Except for herbicides, which were used only at the start of the experiment, all treatments have been applied continuously since 1992. Data of aboveground biomass or coverage per plant species of all herbaceous plants present has been collected annually for several years from 1992.