Nitrogen, Phosphorus, and Potassium Fertilization of Non‐Tilled Maize1

Abstract No‐tillage and conventional tillage (plow, disk, cultivate) were used for corn grown in monoculture for 6 years with three rates of nitrogen fertilization. Phosphorus and potassium were applied uniformly each year with the planter and as surface bulk applications during 2 years of the study. Grain yields were higher for notillage than for conventional tillage treatments at all N levels. Most of the P applied to the soil surface between rows of no‐tillage treatments remained in the surface 2.5 cm of soil. K was also concentrated near the soil surface. P and K concentration in leaves of maize grown without tillage were equal to plants grown with conventional tillage when sampled at tasseling and significantly higher when sampled at the 8 to 10 leaf stage.