REVIEW OF MANAGEMENT AND CONDUCT OF LONG-TERM TILLAGE STUDIES WITH SPECIAL REFERENCE TO A 25-YR EXPERIMENT ON BARLEY IN SCOTLAND

We review the management procedures and conduct of long-term tillage e xperiments in relation to the achievements of a 25-yr experiment estab lished at South Road, near Edinburgh, Scotland, to study soil and barl ey (Hordeum vulgare L.) responses to mouldboard ploughing, chisel plou ghing and zero tillage (direct drilling). We consider experimental obj ectives, design, tillage and fertiliser treatments, agronomic problems , sources of finance, soil sampling, vehicle traffic, weather and econ omics. The application of experimental results to farming practice and the suitability of the soils for non-ploughing tillage are also discu ssed. Trends in soil condition, crop yields, weeds and weather over th e 25-yr period are considered, together with the impact of research fi ndings on fanning practice in Scotland. Recommendations are made for t he planning and conduct of long-term tillage experiments. (C) 1998 Els evier Science B.V.