Wisconsin Corn and Soybean Responses to Fertilizer Placement in Conservation Tillage Systems

There continues to be considerable interest in P and K fertilizer placement among cash grain producers for several reasons. Growers have faced low commodity prices for several years and are interested in certain placement methods that may enhance the efficiency of nutrient use and therefore reduce their input costs. This issue seems be more important in high residue management systems where broadcast, incorporated applications are not possible because there is the need to maintain surface crop residue for conservation purposes. Wisconsin research has shown response to banded P and K in conservation tillage systems. Moncrief (1981) demonstrated a beneficial response to row-placed fertilizer in no-till and ridge-till systems. Bundy and Widen, 1992 demonstrated the importance of using a complete row fertilizer. Recent research conducted by this author demonstrated a response to both falland spring-applied banded fertilizer in high residue systems, but not in a chisel system (Wolkowski, 2000). It seems likely that the soil and environmental condition of the seedbed under no-till increase the potential for response to localized P and K placement.