Eternal cultivation of rye
The " Ewige Roggenbau " is a long-term agricultural experiment that Julius Kühn started in 1878 and has continued to this day. Boldly put the experiment under the influence of the doctrine of Justus von Liebig as pure rye - monoculture on to the long-term effects of mineral fertilizers to examine compared to farmyard manure. The experiment - modified - is continued to this day and is thus the oldest ongoing permanent fertilization experiment in Germany.
In the endurance test is on a scale of Kühn 1878 trial field in Halle Saale of the Institute of Soil Science and Plant Nutrition of the headed Martin-Luther-Universität Halle-Wittenberg continuously winter rye ( Secale cereale L. ) on one of sandy loess hervorgegangenem Parabraunerde- Tschernosem in Self-cultivation with the aim of experimenting with mineral fertilization . The test site is in the black earth region of Saxony-Anhalt , which extends in the eastern Harz foreland .
For decades, the field has consistently provided around one and a half tons of rye per hectare, i.e. around half of the yield that a comparable field achieves with fertilization, even though tens of thousands of potassium, phosphorus and nitrogen are withdrawn from the soil year after year. In 1962, however, Karl Schmalfuß replaced rye self-succession on a third of the plots with continuous maize cultivation and a crop rotation of rye and potatoes in order to be able to measure the adjustment of the humus content to such conditions with other harvest residues.
In Germany there are currently around 30 long-term field tests that cover a wide range of different soil and climatic conditions. A similarly significant test is the " Static fertilization trial " of Wilhelm Schneidewind in Bad Lauchstädt , when it comes to researching the long-term effect of organic and mineral fertilizers on the yields of crops, the quality of the crop and soil fertility. Similar attempts are also known from the British research institute Rothamsted .