Our types of cereals, including wheat, barley, rye, triticale and oat have a strong demand in a micronutrient supply compared to the main nutrient’s nitrogen, phosphorus, potassium and sulphur. Based on an average yield of 80 dt/ha, the nutrient removal of manganese will be 600 to 1000 g/ha, copper around 50 to 150 g/ha, zinc roughly 250 to 350 g/ha and boron around 50 to 100 g/ha. When viewing the extracted amount, these micronutrient removals seems to be low.
Even with a sufficient level in the soil and an application of manure - analysis of many field crops show symptoms for undersupply with nutrients, which is confirmed by many plant analyses of cereals done in the last years in Germany. There are many different reasons for the undersupply with main and micro-nutrients. Most important will be the nutrient availability in the soil solution.