Time of N Application and Yields of Corn in Wet, Alluvial Soils
1975
Miller, John F. | Kavanaugh, John | Thomas, G. W.
Time and rates of N application to corn (Zea mays L.) grown in wet alluvial soils in western Kentucky were studied in the years 1968 through 1972. Two soils representative of the wetter soils in the area were used, Stendal silt loam and Melvin silt loam. The objective of the study was to determine the N fertilization practices that would produce highest corn yields on such soils. The early experiments were concerned with Fall vs. Spring application of N as practiced in the Midwest, but Fall-applied N at lower rates (90 or 112 kg/ha) gave no better yields than the check treatments and even at relatively high N rates (180 and 224 kg/ha) gave such a poor response that this was changed to a comparison between Spring and Summer side-dress applications for the last 2 years. Side-dress application of N was nearly as good as or better than N applied at planting at both locations, although increasing the N rate at planting tended to obscure this effect. The results show that Summer side-dressing of N on corn grown in wet soils is an effective way of fertilizing corn. They also suggest that late N application on corn made severely N deficient by excessive rain is an excellent practice.
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