Plowing Effect on Corn Yield Response to N Following Alfalfa
1979
Triplett, G. B. | Haghiri, F. | Van Doren, D. M.
Meadow crops traditionally are destroyed and incorporated into the soil for grain crop production by moldboard plowing. With no-tillage crop production, vegetation is destroyed with herbicides and remains physically undisturbed. Such changes in management practices could influence release of nitrogen to the grain crop that follows. An experiment was designed to evaluate the response of corn grown for grain to N fertilizer rates under plowed and non-tilled conditions on a Wooster silt loam, a fine-loamy, mixed, mesic typic Fragiudalf soil. Nitrogen at rates of 0, 28, 56, 112, and 168 kg/ha was applied to corn (Zea mays I,.) following an alfalfa (Medicago sativa L.) meadow and planted with either notillage or into soil that was moldboard plowed. In a field experiment of 3-year duration, corn yield was increased by added N only in 1 year at the 56 kg/ha N level. No interaction of tillage and N rate occurred, indicating tillage was not necessary to release N contained in the legume crop During one growing season with adequate amounts of rainfall, corn yields greater than 90 quintals/ha were produced without added N. Meadows containing an excellent stand of legumes are capable of supplying most, if not all, of the N needs for the grain crop that follows. This was true for rotation studies reported in the 1930's and 1940's when corn yields of 40 to 60 quintals/ha were common and seems to be true today when yield levels are almost double.
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