Effect of Lime Application on No‐Tillage and Conventionally Tilled Corn1

Abstract

AbstractSoil management to control soil acidity resulting from surface applied N fertilizer is an important factor in continuous no‐tillage corn (Zea mays L.) production. The objective of this study was to evaluate the effectiveness of surface‐applied lime in maintaining a favorable soil pH level under continuous no‐tillage and conventional tillage corn systems.Experiment 1 was established in 1971 on a moderately well‐drained Tilsit silt loam (Typic Fragiudults) soil. Lime treatments for both no‐tillage and conventional tillage included: (1) 0 (check), (2) 3.36 mt/ha, (3) 10.08 (4) 3.36 initially + 1.12 mt/ha applied each year, (5) 3.36 initially + 2.24 mt/ha applied every year, and (6) 3.36 initially + 3.36 mt/ha applied after 3 years. After 5 years of continuous no‐tillage corn production the soil surface receiving no lime became extremely acid, pH 4.6. In the no‐tillage plots lime additions resulted in a statistically significant increase in grain yield. Little difference was observed for yield or soil pH changes for the lime treatments that included different frequencies of application. The lime rate based on a soil buffer test recommendation of 3.36 mt/ha was effective in maintaining favorable soil pH and yield levels.Comparison of limed and unlimed treatments in Experiment 2 on deep, well‐drained Maury (Typic Paleu‐ dalfs) soil showed increased yields for liming no‐tillage plots as N‐rates increased, but no significant yield response for lime on conventionally tilled treatments. The surface soil pH level decreased to pH 4.3 on unlimed, no‐ tillage treatments receiving 336 kg N/ha after 7 years of continuous corn. It is concluded that surface liming without incorporation is an efficient way to overcome soil acidity caused by N fertilization of no‐tillage corn.