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Zinc sulfate (ZnSO4 · H2O) has traditionally been the “reliable” source of zinc (Zn) fertilizer, but other sources of Zn are also available. Some are derived from industrial by‐products, varying from flue dust reacted with sulfuric acid to organic compounds derived from the paper industry. The degree of Zn mobility in Zn sources derived from these various by‐products is related to the manufacturing process, the source of complexing or chelating agents (organic sources), and the original product used as the Zn source. Many claims are made regarding the relative efficiency of traditional inorganic Zn fertilizers and complexed Zn sources. The objective of this column study was to compare the mobility of several commercial Zn fertilizer materials (organic and inorganic) that are commonly used to correct Zn deficiencies in soils. The sources included three granular inorganic Zn sources, two granular organically complexed Zn sources, and liquid ZnEDTA. Soil columns were leached five times with deionize...

Micronutrient deficiencies in plants are common throughout the world. Many inorganic and organic fertilizers are manufactured and applied to soils and plants to correct micronutrient deficiencies. The objective of this article is to review current research and present our findings on factors that affect micronutrient fertilizer efficacy. In the United States, state laws regulate the “guarantee analysis” of fertilizers and essentially all states require that manufacturers meet a total analysis requirement. However, there is no consideration of micronutrient “availability” in this analysis. Our research has shown that Zn availability in granular fertilizer was related to water solubility (r2=0.92) and not total Zn content. The relative availability coefficients for organic and inorganic Zn fertilizers was also highly related to water solubility and independent of total Zn content. Because of this discrepancy, there are fertilizers in the marketplace that are very low in plant available micronutrien...

Alternatives to landfilling fly ash may be to use it as a soil amendment since it is fine textured and could alter soil texture and thus improve water retention. However, fly ash contains elevated B, soluble salts, and trace element concentrations that could adversely affect plant and soil quality. Objectives were to characterize leaching of soluble salts, plant nutrients, and trace elements in a sandy soil amended with a high rate of fly ash ({approximately}662 Mg ha{sup -1}). We established Field plots in an Evesboro loamy sand using typical agricultural equipment. Lysimeters were installed to a depth of 120 cm and used to collect leachate over a 9 mo period. We also used microplots; (1.0 by 1.0 m) and similar ash rates to characterize leaching under controlled conditions. Lysimeters were installed at four depths in each microplot (15, 30, 60, and 120 cm) and water applied with a rainfall simulator. Boron and soluble salts were leached from the rooting zone after {approximately}38 cm of natural rainfall or 42 cm of irrigation. Calcium and S were the dominant plant macronutrients in leachates while Cu, Mn, and Zn were the only detectable micronutrients. Peak concentrations of these elements were detected after {approximately}50more » cm of rainfall or irrigation and decreased to below or near initial concentrations by the conclusion of the study. Nickel was the only detectable trace element in leachates, however, concentrations were variable and