To evaluate the yield and profitability of applying various forms of nitrogen (N) to soybeans at various growth stages.

2016 Kentucky Soybean Nitrogen Timing Study

At other locations where we have multi-year data on this study, we have discovered a pattern:

Supplemental N applications have the most impact on yield when the applications precede extended periods of saturated soil conditions. We definitely experienced our fair share of saturated, anaerobic soil conditions in Kentucky this year.

The key difference in 2016 was we had so much rain immediately following the V6 N application that it leached out of the soil root zone before it dried out enough for the plants to resume uptake.

By the R4 growth stage, yield was already limited due to excessive rainfall and additional N late in the season showed no yield increase.

Fall Chisel, Spring Vertical-Till/Field Cultivation | 

 Burndown: 1 qt. Roundup WeatherMAX® Pre: 8 oz. Authority® Assist Post: 4 oz. Section® Three, 27 oz. Flexstar® GT 3.5, 0.3 oz. FirstRate® | 

2021 Iowa Soybean SINGULATION STUDY 15 IN. ROWS

2021 Iowa Soybean STARTER FERTILIZER STUDY 2X2X2

Nitrogen Timing Study