Continuous corn production using conservation tillage often results in less uniform and smaller early season growth along with lower grain yields and profitability. This is especially true on fine-textured and poorly drained soils in the northern part of the Corn Belt where decomposition of surface residues is slower and soil temps are colder. The primary objective of this study was to determine the effects of fluid starter fertilizer combinations and placement of 10-34-0 (APP), 28-0-0 (UAN),

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... d 12-0-0-26 (ATS) on second-year corn production in reduced tillage/high-residue conditions. Two field experiments, one on a Webster clay loam soil at Waseca and another on a Mt Carroll silt loam near Rochester, were established in April of 2010. Twelve of the 14 total treatments were comprised of a factorial combination of rates of three fluid starter fertilizers: 0 or 4 gal/ac of APP, 0 or 8 gal/ac of UAN, and 0, 2, and 4 gal/ac of ATS. The APP was applied in-furrow with the seed while UAN and ATS were applied as a dribble band on the soil surface within 2" of the seed row. Corn was planted at 35,000 seeds/ac on May 3 at Waseca and April 27 at Rochester. At V2-3 UAN was injected 3" deep midway between the rows to give a total (at planting + V2-3) N rate of 180 lb/ac on all plots. At V7-8 stage corn plants were harvested from each plot to determine dry matter yield, and the plant tissue was analyzed for N, P, K and S concentration. Grain yield and moisture content were determined by combine harvesting. Grain samples were analyzed for N, P, K and S concentration. A record wet June and July at Waseca stressed corn and may have reduced yield potential. Crop response to treatments varied markedly between locations. Early plant growth (plant heights and dry matter yields) were enhanced when N, P and S starter fertilizers as APP, UAN and ATS were applied at the Waseca site. Whereas only APP application affected early plant growth at Rochester. Grain moisture was reduced about 1.0 percentage points when APP or UAN were applied at Waseca, while moisture was reduced 1.5 and 2.5 percentage points with the 2 and 4 gal/ac rate of ATS, respectively, compared with 0 gal/ac. At Rochester, grain moisture was reduced about 1 percentage point with APP, slightly with UAN, and was not affected by ATS application. Corn grain yields were 6 to 9 bu/A greater with ATS (sulfur fertilization) at Waseca, when averaged across APP and UAN treatments. A significant UAN×ATS interaction for grain yield showed when UAN was not applied at planting, grain yields increased about 18 bu/ac with ATS fertilization. When UAN was applied, no yield response to ATS was observed. At Waseca adding 1 gal/ac of ATS to 4 gal/ac of APP applied in-furrow increased grain yields 12 bu/ac compared with APP alone and final plant populations were not reduced significantly. No grain yield responses to N, P, and S starter fertilizer treatments were found at Rochester.