Tillage might result in some sort-term gains, but soil scientist Jay Fuhrer warns that the practice causes long-term damage to healthy soil’s best friend — fungi.

When it comes to crop production, averages don’t work as a guide for fertilizing and controlling weeds or pests. If a grower collects data and then uses averages as a guide, the field will be over-fertilized in some places and under-fertilized in others.

Corn and soybean take up relatively large amounts of phosphorus (P) and potassium (K), and much of this P and K ends up in the grain that is taken off the field during harvest. In order to keep soil nutrient levels from dropping over time, the amounts removed need to be replaced by applying fertilizer or manure. In order to know how much nutrient a crop removes, we need to know how much there is in a bushel of harvested grain.

Research by a U.S. Department of Agriculture (USDA) scientist provides new information about how long those plant nutrients remain after biosolids have been applied to the soil.