'Eternal Rye' soil nutrient content and pH value since 1878

This dataset contains the soil data of C, N, P, K, Mg, and the pH value of the “Eternal Rye” long-term experiment in the years 1878-2006, the harvest and the soil sampling dates and information about the fertilization treatments. The first sampling took place before the implementation of the field trial in 1878. In 1959 no crops were grown. 
The field trial originally consisted of five plots with different fertilizer applications. In all plots each year winter rye was grown, treatments are not replicated. In some years multiple replicates of soil samples were taken within the plot. The treatments include mineral N, PK, and NPK fertilization, organic fertilization with farmyard manure (FM_I), and an unfertilized plot (U). In 1893 an additional plot with reduced organic fertilization was added (FM_II). Here, fertilization was ended after the harvest of 1953. The plot is unfertilized ever since. In 1991 a combined fertilization of mineral NPK and farmyard manure (NPK_FM) replaced the N plot, and the nitrogen amount in the NPK plot was increased from 40 to 60 kg N/ha/a. In 1961 the plots were divided into three sections, in one of which (Section C) the winter rye monoculture was continued. In 1985 lime (2.77 t/ha CaO) was applied to all plots of section C in order to reach a pH value of 6.2. The data set includes data of the large plots until the separation and the section with continued winter rye monoculture hereafter. The trial is managed under conventional farming methods, with chemical and mechanical pest control as needed. 
P and K have been extracted using the Double-Lactate (DL) extraction method since 1929. For the samples before that (1878, 1912) no information about the method is available any more.