• The leading blended treatment delivered the highest milk and beef output per hectare, indicating superior conversion of applied nitrogen into productive biomass.

• Dry matter yield under blended programs was comparable to, or exceeded, standard UAN treatments, confirming no yield penalty from reduced fertiliser spend.

• Total fertiliser cost for blended programs was materially lower than UAN-only strategies, improving margin without compromising output.

• Forage quality metrics (Neutral Detergent Fiber,  Neutral Detergent Fiber Digestibility (30-hour), starch) varied by treatment but did not directly correlate with net return, reinforcing the importance of whole-system efficiency.

• UAN-only programs remained yield-competitive but showed lower nitrogen-use efficiency when assessed on output and return per unit of applied input.

• Results support the role of blended nitrogen strategies in improving economic efficiency through source and timing optimisation rather than increased application rate.

Trial Design and Context

This study evaluated six nitrogen strategies applied to corn, including UAN-only programs, Green Lightning–only programs, and blended UAN/Green Lightning approaches. Treatments were applied at defined growth stages (2x2 and V3) to assess not only yield response, but whole-system performance.

Measurements extended beyond dry matter yield to include forage quality parameters (NDF, NDFD 30 hr, starch), milk and beef output per hectare, fertiliser cost, and net economic return. This allows nitrogen strategies to be assessed on productivity efficiency rather than yield alone.

Yield and Forage Quality Outcomes

Dry matter yield differed across nitrogen strategies, but the spread between the highest and lowest performing productive treatments was relatively narrow. Standard UAN produced 22.15 t DM/ha, while the highest-yielding program (60 units GL at 2×2 with 130 units UAN at V3) reached 22.42 t DM/ha, a difference of 0.27 t/ha.

The blended 50/50 GL/UAN program achieved 22.80 t DM/ha, exceeding standard UAN by 0.65 t/ha while operating at a substantially lower fertiliser cost. This confirms that blended strategies were able to match or exceed UAN yield without increasing total nitrogen input.

Forage quality metrics varied by treatment. NDF ranged from 34.1 to 45.8%, while NDFD 30 hr ranged from 54.9 to 58.8%. The highest-return treatments did not consistently lead individual quality categories, reinforcing that economic performance was driven by system efficiency rather than a single forage parameter.

Milk and Beef Production Efficiency

Differences between treatments became more pronounced when performance was expressed as productive output per hectare.

Standard UAN generated 31,683 kg milk/ha and 2,610 kg beef/ha. In contrast, the 50/50 GL/UAN blend delivered 36,648 kg milk/ha and 3,352 kg beef/ha, representing increases of approximately +4,965 kg milk/ha and +742 kg beef/ha relative to UAN.

The GL-led program (60 units GL at 2×2 with 130 units UAN at V3) also outperformed standard UAN, producing 33,547 kg milk/ha with a lower total fertiliser cost. These results indicate that blended and GL-integrated programs converted applied nitrogen into animal-usable energy more effectively than single-source UAN.

Cost Structure and Net Return

Fertiliser cost was a major driver of net return differences.

Standard UAN:
  Total fertiliser cost: $988/ha
  Net return: $19,275/ha

GL-led program (60 GL + 130 UAN):
  Total fertiliser cost: $683/ha
  Net return: $20,565/ha
  Net gain over UAN: +$1,290/ha

50/50 GL/UAN blend:
  Total fertiliser cost: $505/ha
  Net return: $22,566/ha
  Net gain over UAN: +$3,291/ha

Despite operating at $483/ha lower fertiliser cost than UAN, the blended program delivered the highest production and the strongest economic outcome.

The outcome shown above is not an isolated result. Similar yield and economic responses have been observed across multiple independent trials, seasons, and crop types. In each case, programs using blended Green Lightning and UAN consistently matched or outperformed single-source nitrogen strategies.

This repeated performance across different environments strengthens the conclusion that GL/UAN blends are not a one-off success, but a repeatable approach to improving nitrogen efficiency and overall return.

Summary

Across the six nitrogen strategies evaluated, differences in dry matter yield were relatively modest, with blended UAN and Green Lightning programs matching or exceeding standard UAN tonnage while operating at substantially lower fertiliser cost. When performance was assessed on a whole-system basis, incorporating yield, milk and beef output, and input cost, the blended strategies delivered a clear economic advantage. The 50/50 UAN/Green Lightning program produced higher productive output per hectare and improved nitrogen-use efficiency, resulting in net returns more than $3,000/ha above standard UAN. These results demonstrate that optimising nitrogen source and timing can improve profitability without increasing total nitrogen input.