Multi-Year Nitrogen Rate & Placement Corn Study

Nitrogen application during planting with Conceal

Key Points

Objective: This 7-year long-term study evaluates the performance of nine different nitrogen rate and placement programs. These nine programs consist of single one-and-done nitrogen programs, 2-way split applications, and even 3-way split programs. All treatments are applied using 32% UAN liquid nitrogen. As a baseline, the 50% WNF + 50% V6 Side-Dress (Treatment #4) is facilitated as the control for this trial.
Split Application Advantages: When we are adding a dual application side-dress treatment in addition to a WNF program, it has offered 12.8 Bu/A average yield advantages. If we take this one step further, adding a planter-applied application (triple split) offered even higher average yields gains at 26.0 Bu/A.
Highest Performer: The top nitrogen program over the 7-year period was the triple split program (Treatment #9), which has resulted in an economic increase of $48.77/A compared to the 50% WNF + 50% side-dress control (Program #4).

Single Applications:

1) 100% Weed-N-Feed (WNF)	240# N as Surface applied 32% UAN
2) 100% Conceal Single Band	240# N with Conceal Single N Band 1.5” Deep
3) 100% Conceal Dual Band	240# N with Conceal Dual N Bands 1.5” Deep

Dual Split Applications:

4) 50% WNF + 50% SideDress (SD)	120# N WNF+ 120# N V6 Side-Dress “Control”
5) 50% Conceal Single Band + 50% SD	120# N Conceal Dual Bands + 120# N V6 SD
6) 50% Conceal Dual Band + 50% SD	120# N Conceal Dual Bands + 120# N V6 SD
7) 25% Conceal Dual Band +50% SD	60# N Conceal Dual Bands + 120# V6 SD
8) 75% Conceal Dual Band + 50% SD	180# N Conceal Dual Bands + 120# N V6 SD

Triple Split Applications:

9) 25% Conceal + 25% WNF + 50% SD

90# N WNF + 90# N Conceal Dual Bands + 120# SD

In this multi-year study, we're evaluating the performance of nine (yes, nine!) different nitrogen rate and placement programs. These nine programs consist of single one-and-done nitrogen programs, 2-way split applications, and even 3-way split programs.

In this study, all treatments are applied using 32% UAN liquid nitrogen. As a baseline, the 50% WNF + 50% V6 Side-Dress (Treatment #4) is facilitated as the control for this trial.

When we average the data since 2017, the single nitrogen applications performed the lowest along with the 25% reduced rate treatment (#7: 25% Conceal Dual Band+50% SD). In contrast, the Triple Split nitrogen rate treatment (#9) saw the highest overall yield at a 243.3 Bu/A average. Our control performed at 230.1 Bu/A for comparison. Just three performed above our control group when it comes to yield.

Chart showing yield comparison between nitrogen applications 2017-2023 at the PTI Farm

The story continues as we calculate net return after the cost of nitrogen. The top nitrogen program was the triple split program (Treatment #9) and has resulted in positive economic returns of +$48.77/A in comparison to our control.

To understand the efficiency of the applications, we evaluated adjusting the nitrogen rate by +25% and -25%. Adding 25% more nitrogen was the 2nd overall highest-yielding treatment, and also resulted in the 2nd highest overall net return after the cost of N, albeit -$21.64/A less than the top triple split program.

Lowering the nitrogen rate by 25% has turned out costly, as yields have suffered -13.0 Bu/A along with decreased returns of -$38.05/A compared to the control. However, this -25% reduced rate of N still offered +$3.57/A above the single application 100% WNF rate of nitrogen.

Overall, single application nitrogen programs posted negative economic returns of -$19.52/A, -$21.04/A, and -$34.93/A.

Chart showing economic comparison between nitrogen applications 2017-2023 at the PTI Farm

Our triple split application clearly offers the advantage with 26.0 Bu/A compared to the 100% WNF application. The dual application side-dress treatment also offered a 12.8 Bu/A yield advantage above the 100% WNF application.