The Woburn Ley-arable experiment, 1938-2020: its management, the issues and problems that arose, and their resolution to maintain the continuity and relevance of the experiment.

The Woburn Ley-arable experiment is the oldest of its type in the UK, and data from it has been used widely. It is a complicated experiment, and there have been many changes over the years to cropping, fertilizer and farmyard manure (FYM) applications, to ensure its continued use and relevance to agricultural practice. It was designed initially to test the effects of rotations with or without leys (short-term herbage) on the yield of arable test crops. It is now an important resource for investigating long-term changes in soil organic matter (SOM) due to different cropping systems. It consists of 40 pairs of main plots, half of which are in ‘Continuous Rotations’, and half originally in ‘Alternating Rotations’. The Alternating Rotation plots gave little additional information, so they were replaced by longer term leys in 1973. Changes to the treatment rotations, test crops and lime, FYM and fertilizers applied over the years, are described here. This paper attempts to detail the important changes that have been made in the management of the Woburn Ley-arable experiment to ensure that it remains relevant to current issues in soil fertility, crop yield and carbon storage. A list of the major changes, in chronological order, is given in Appendix Table 3.