GRDC National Risk Management Initiative (RiskWi$e) NSW – Action Research Group (ARG) Nitrogen Management Systems Trial – Zone 3
GRDC National Risk Management Initiative (RiskWi$e): NSW Action Research Group (ARG) – 2023 to 2028
NSW ARG is led by CSU, with the project funded by GRDC.
The national RiskWi$e initiative is a long term GRDC funded project, aimed at improving decision making for grain growers by helping them to better understand and manage risk.
For more information on the national RiskWi$e project please click on the link below:
Theme 1: Nitrogen Management Systems Trial – Zone 3
Grower engagement by Ag Grow Agronomy identified N as their number 1 issue and their biggest expense. This has provided direction for theme 1 of the project.
2025 is the third year of the Griffith N systems trial, set up to test the performance of different nitrogen management strategies over the long-term. This site is one of 10 throughout NSW.
Nitrogen application strategies in the trial will test N management decisions that inform risk-reward, in terms of productivity (yield, protein), profitability (gross margin, risk) and sustainability (soil organic matter, carbon footprint, N losses). The strategies are a combination of N banking treatments, tactical seasonal approaches, replacement strategies and benchmark treatments such as grower practice and Nil. The trial 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:
- Nil N Control – Starter fertiliser (e.g. MAP) at sowing only
- Grower Practice – N rate determined by local N decision making process
- Low Risk Seasonally Responsive – Sufficient N applied to meet water limited potential yield assuming a decile 2-3 season finish; using Yield Prophet® assuming decile 2-3 rain (moderate drought)
- Moderate Risk Seasonally Responsive – Sufficient N applied to meet water limited potential yield assuming a decile 5 season finish; Yield Prophet® decile 5 rain (median)
- High Risk Seasonally Responsive – Sufficient N applied to meet water limited potential yield assuming a decile 7-8 season finish; using Yield Prophet® decile 7-8 rain (favourable)
- Seasonal Forecast Responsive – using Yield Prophet® informed by Bureau of Meteorology 3-month seasonal forecast
- 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
- Replacement – apply N fertiliser equal to grain N offtake from previous season
- Replacement +30% – apply N fertiliser equal to grain N offtake from previous season plus 30%
- Replacement -30% – apply N fertiliser equal to grain N offtake from previous season minus 30%
- Manure – proportion of N supplied through addition of manure of known N content.
- Enhanced fertilisers – N fertiliser is supplied with coatings to reduce losses
