Northeast Research and Demonstration Farm
No-till management can change many soil properties and crop yield compared with tillage. Because broadcast phosphorus (P) and potassium (K) fertilization with no-till results in significant accumulation of both nutrients at or near the soil surface, subsurface band application could be more effective. A study was initiated in 1994 to compare no-till and chisel-plow tillage and fertilizer placement methods for a corn-soybean rotation. The soil at the experimental area is Floyd loam, and initially tested Very High in P (33 ppm, Bray- 1) and Optimum in K (140 ppm). The study includes four trials: P for corn, P for soybean, K for corn, and K for soybean. Both crops are grown each year by alternating adjacent areas, and treatments are applied for both crops. The crops are planted using a 30-in. row spacing. Cornstalks of plots managed with tillage are chisel-plowed in the fall and field cultivated in spring, whereas soybean residues only are field cultivated in spring.
Iowa State University
Mallarino, Antonio P. and Pecinovsky, Kenneth T., "Long-term Phosphorus and Potassium Placement Methods and Tillage Effects on Yield of Corn and Soybean" (2011). Iowa State Research Farm Progress Reports. 237.