In season sulfur application at Top hill of Field

This research took place on the top hill of a field in Minnehaha County. Soybeans were planted in 30-inch rows at 160,000 seeds per acre on May 15, 2020. Nitrogen with sulfur fertilizer and Nitrogen without sulfur fertilizer were the two treatments used in this experiment. Nitrogen and sulfur fertilizer were combined at 30 lb/ac and 15 lb/ac, respectively, and applied at the R3 growth stage for nitrogen with sulfur treatment, while nitrogen fertilizer was applied alone at 30 lb/ac at the same time for nitrogen without sulfur treatment. Polymer coated urea and ammonium sulfate is used as nitrogen and sulfur fertilizer sources, respectively. There were four replications of each fertilizer treatment. For this experiment, the plot was 10 feet wide by 30 feet deep. The combined application of nitrogen and sulfur treatment was subtracted from nitrogen treatment to calculate the effect of sulfur on soybean yield.

Overall, at top hill of the field, nitrogen with sulfur increase the yields by 2.5 bu/ac (Table 1), however statistically it was not significant. Rep, 4 had a decrease in yield by -6.9 bu/ac compared to due to combined effect of Nitrogen and sulfur fertilizer, whereas Rep 1, 2 and 3 had increased yield. Additional trials with more replications should be completed to identify efficacy of treatment over multiple years.