GRDC National Risk Management Initiative (RiskWi$e) NSW – Action Research Group (ARG) Nitrogen Management Systems Trial – Zone 3
Collaborating with CWFS, FarmLink and CSU, this project is funded by GRDC.
This project is part of ‘RiskWi$e’ (the National Risk Management Initiative) and focuses on risk and reward, with research carried out in action research groups (ARG).
As part of the NSW ARG, and as part of the Nitrogen Theme, Ag Grow Agronomy set up a nitrogen (N) systems trial in 2023 to test the performance of different nitrogen management strategies over a four-year period. Grower engagement by Ag Grow Agronomy identified N as their number 1 issue and their biggest expense. Which gave direction to theme 1 for the first year of the project. This trial will test N management decisions to inform risk-reward as well as compare N banking to existing N demand strategies.
The aim of the trials is to compare the productivity (yield, protein), profitability (gross margin, risk) and sustainability (soil organic matter, carbon footprint, N losses) of different management systems over the long term (>5 years). They will also provide information on whether fertiliser N not used
by crops in year of application carries over to subsequent seasons, what the consequences of excessive N fertiliser are for crop productivity, and the effect of different N fertiliser strategies on legume productivity and N fixation. The Griffith N Systems trial consists of 12 treatments including:
1. Nil N Control
2. Grower Practice
3. Low Risk Seasonally Responsive – assuming a decile 2-3 season finish
4. Moderate Risk Seasonally Responsive – assuming a decile 5 season finish
5. High Risk Seasonally Responsive – assuming a decile 7-8 season finish
6. Seasonal Forecast Responsive
7. Financially Responsive – apply as much N fertiliser as can be purchased with 8% of gross
income from the previous season at current market value of urea
8. Replacement – apply N fertiliser equal to 2022 grain N offtake
9. Replacement +30% – apply N fertiliser equal to 2022 grain N offtake plus 30%
10. Replacement -30% – apply N fertiliser equal to 2022 grain N offtake minus 30%
11. Manure – of known N content.
12. Enhanced fertilisers – N fertiliser with coatings to reduce losses