This publication should answer many of the questions facing crop producers and fertilizer suppliers regarding nutrient management in a continuous no-till production system. Some assumptions must be made when discussing no-till. The first is that in continuous no-till systems, a buildup of plant residues on the soil surface will occur. These residues provide protection against soil erosion. Whether in a cropping system of soybean, soybean-wheat and corn or sorghum rotation, the assumption is that considerable residue will be covering the soil surface after corn or sorghum planting.
Some states now suggest taking a soil sample to a shallower depth for no-till.
In Missouri, however, the routine sampling depth is still preferred when interpreting soil sample results and making fertilizer recommendations because of past calibration research. The best producers are learning the value of taking several soil samples from one field and mapping soil fertility within the field. This information can be extremely valuable. Dramatic adjustments to fertilizer inputs can be made while still improving yields, especially on fields that generally test high in phosphate and potash. One soil sample is composited from each of the grid areas to help identify soil fertility variation within the field.