Abstract: | Site effects of small-scale yield variation in the Tertiary hills north of Munich (Germany) and conclusions for site specific farming The effect of numerous soil factors on small-scale yield variation of winter wheat and spring barley were examined: soil structure and soil texture, soil nitrate content and soil water at different times, PCAL-, KCAL-, Nt- and Ct-content, pH, soil microbiology characteristics, relief, root growth and important plant diseases. The varying annual influence of soil parameters on crop yield was interrelated with climatic factors. In soils with low sand content soil productivity was largely influenced by soil structure. This effect was less pronounced on soils with medium sand content. On sandy soils, however, yield was reduced by available water capacity. Yield potential was also lowered by frequent cereal growing associated with take-all root desease of winter wheat. High yield variation from year to year confirmed that a site-specific crop management should consider annual variability of yield in addition to soil conditions and yield measurement. Site-specific N fertilization should be adapted to the actual progress of plant growth. |