Proceedings
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| Filter results4 paper(s) found. |
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1. Economic Optimum Rates of N for Corn Production in IowaProper nitronen (N) fertilizer is essential if crop producers are to maximize profits and minimize environmental contamination. A study to determine 'economic optimum N fertilizer rates was conducted in Iowa from-1987 to 1991. The results show that Iowa crop producers over-applied N during those years primarily due to not considering residual N in the soil. This was especially true following the drought year of 1988.... |
2. Response of Corn Grown in Two Crop Rotations to Different N Rates and NitrapyrinNitrogen fertilization of corn is necessary to obtain adequate yields. Loss of soil-applied N1-L'-N fertilizers due to nitrification can decrease corn yield significantly. Nitrate contamination of ground or surface water supplies should also be considered. Use of nitrapyrin may help address these issues, though in fine textured soils response to its use is difficult to predict. A 10-year study was done to determine the effects of annual application of ammonia with nitrapyrin upon the yield of continuous... |
3. Spatial Response of Corn to Banded Zinc Sulfate Fertilizer in IowaThe solubility of zinc (Zn) decreases as pH increases. There are soil associations that contain high pH spots within fields where the surrounding soils' pHs are slightly acid. It is reasonable to expect that Zn availability, due to a difference in solubility, is different in the two areas. The objectives of this study were to find corn (Zea nlnys L.) grain yield responses to Zn fertilizers within fields and to define the soil characteristics in responsive areas. The study was conducted at twelve... |
4. Soil Electrical Conductivity Map Quality- Impact of Interpolation Search Neighborhood ParametersSpatial predictions of soil electrical conductivity (EC) measurements may be improved by adjusting the search neighborhood criteria. The objective of this study was to investigate how varying search parameters impacted the quality of soil EC maps. The three fields cl~osen for this study were from the Inner and Outer Blue Grass physiographic regions of Kentucky. Soil EC was measured by direct contact at all locations. The prediction datasets included EC measurements along transects that were separated... |