Proceedings
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| Filter results3 paper(s) found. |
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1. Preplant Soil Nitrogen Test for CornSoil ammonium N and nitrate N were measured at the pre-plant and sidedress stages on 59 Michigan fields in 1992. Total inorganic soil N (ammonium N plus nitrate N) at pre-plant stage averaged to 12.6 ppm, about 50% of which was present in the nitrate form and 50% in the ammonium form. Total inorganic N at sidedress stage was 18.9 ppm, of which the nitrate N component was 12.2 ppm. The NH JNO, ratio decreased from 1.06 at prep1 ant stage to 0.54 at sidedress stage. Multiple correlation analysis revealed... |
2. Overview of Manure Handling on Steroid Movement in Agricultural Fields from Beef Cattle SystemsManure generated from concentrated animal feeding operations may serve as a source of steroids in surface water and potentially in groundwater. The objectives of this research were to determine the amount of steroids and metabolites in runoff from beef cattle production pens, and from runoff and leaching from crop production fields. Cattle were fed a synthetic progestagen, MGA or melengestrol acetate and treated with zeranol, trenbolone acetate, and estradiol implants, while a second group was not... |
3. Relationship of in-season soil nitrogen concentration with corn yield and potential nitrogen lossesModeled or measured soil mineral N (SMN) levels during the corn growing season have been used to set sidedress N rates, but there has been little research linking SMN levels at different growth stages to yield to help guide this process. The degree to which SMN level influences the risk of N losses is also not known. Data from 32 site-years of field experiments in Illinois (2015–2018) that included 12 combinations of N fertilizer rate, timing, and source, were used to evaluate... G. Preza-fontes, E. Nafziger, L. Christianson, C. Pittelkow |