What effect do different tillage systems have on soil pH?
All lime calculations are based on neutralizing the acidity in the top six inches of soil. As a result, different tillage systems affect soil acidity. A conventional tillage system involves several tillage passes over the field prior to planting. If the subsoil is calcareous, deep tillage may mix enough subsoil into the top six inches to maintain soil pH at the surface. Conventional tillage systems allow the opportunity to thoroughly mix applied lime prior to the next growing season. A conservation tillage system is not as aggressive as conventional. Fewer tillage passes may be implemented prior to planting, leaving greater than 30 percent crop residue on the soil surface. As a result, there is a limited amount of soil mixing. It is critical to closely monitor soil pH in no-till systems since most lime and dry fertilizer is surface-applied. Over time, the top inch of soil may become extremely acidic due to the surface application of fertilizer. However, soil surface pH can also become
