Armstrong Research and Demonstration Farm
A three-year study was conducted to evaluate the efficiency of fall or spring broadcast phosphorus (P) fertilization for no-till corn and soybean. Some believe broadcast fertilization is a less efficient placement method than banding for no-till because P tends to accumulate at or near the soil surface. However, long-term research has shown no difference between band and broadcast P fertilizer placement methods for no-till or chisel-plow tillage, even with significant stratification of soil-test P. One possible explanation for this result is that broadcast P was always applied in the fall. Such application date in advance to planting the crops could provide sufficient time for fertilizer granules or dissolved P movement below the residue cover as a result of rain, freezing and thawing, and/or macrofauna activity. Therefore, this study was planned to test this hypothesis by comparing broadcast fertilization in fall and spring for no-till corn and soybean.
Iowa State University
Mallarino, Antonio P.; Butler, Jeff; and Havlovic, Bernard J., "Effect of Phosphorus Fertilizer Broadcast in Fall or Spring on Yields of No-Till Corn and Soybean" (2008). Iowa State Research Farm Progress Reports. 648.