The Askov long-term experiments: 1894-2019
DCA rapport, nr. 151, 2019
Af Bent T. Christensen, Ingrid K. Thomsen and Jørgen Eriksen
Established in 1894, The Askov Long-Term Experiments on Animal Manure and Mineral Fertilizers (Askov-LTE) is among the very few agricultural experiments with treatments continued beyond 125 years. The Askov-LTE remains the only known experiment maintained for more than a century that allows a direct comparison of incremental and corresponding rates of N, P, and K in animal manure and mineral fertilizers. Another unique feature is the field layout. In contrast to other experiments of similar age, the Askov-LTE includes four replicate blocks (fields) with abundant treatment replicates within each block. This allows the significance of treatment effects be tested thoroughly by statistical analyses.
Records of crop yields stretch back to the start of the experiments in 1894, while systematic sampling and archiving of soil at 4 years intervals began in 1923. Archiving of crop samples began in 1949. Encompassing results from routine soil and plant analyses, archived soil and plant samples, a detailed documentation of changes in treatments and general field management, recordings of climate parameters, and an extensive backlog of results obtained in specific projects, the Askov-LTE provides a unique research platform for studies in very diverse scientific disciplines.