Enterprise choice and sequence strategies that drive sustainable and profitable southern Australian farming systems
Southern Farming Systems Project
Edillilie Site – Lower Eyre Peninsula
Farm profitability can be improved by identifying the factors that drive profit and adopting management that optimises returns and mitigates risks. Growers are under mounting pressure to maintain profitability due to constraints such as input costs, herbicide resistance, declining soil fertility, increasing soil-borne pathogens and climatic variability.
Employing a farming systems approach allows for assessing strategic options (enterprise choice, sequence, livestock integration, risk positioning, GHG mitigation) and tactical decisions (time of sowing, fertiliser application, crop protection) over time. Growers lack the means to fully test all available enterprise choices, potentially leading to short-term gains with long-term consequences for profitability. Crop type and sequence impact yearly profitability, while lasting effects of sequence and fertiliser strategy drive long-term farming system profitability. Australian farmers use crop benchmarking tools to compare individual crop performance to potential in water-limited conditions, but resource efficiency and carry-over effects on water, N, weeds, and disease across years are crucial in dryland farming systems.
Farming systems investments (DAQ2007-004RMX; CSP2110-004RMX) in the GRDC Northern Region show that integrating field research, modelling, and economic analysis highlights opportunities and risks for system profitability. Different farming systems in diverse environments can be compared for factors like WUE (water use efficiency), disease impact, weed control, and nutrition management. Contrasting systems with varied treatments across sub-regions, measured using common metrics, empower growers with informed decision-making. This investment aims to gather comprehensive data for calculating modern and emerging farming systems.
The Southern Farming Systems project, that commenced in 2023 consists of:
- 4 core sites, where 10-14 systems are being evaluated, with more intensive data collection and analysis. These are located at Hart (SA), Manangatang (Vic), Birchip (Vic), and Streatham (Vic).
- 5 satellite sites, where 3-7 systems are being evaluated, with less intensive data collection and analysis. These are located Booleroo (SA), Wallup (Vic), Edillilie (SA), Warrambine (Vic), and Roseworthy (SA).
This project is not trying to ‘re-invent the wheel’. The aim is to leverage the large amount of work in the past on cropping sequences and build on this to look at the value/sustainability/risk of different systems. The field trials will set out to shed new light on drivers of profitability and sustainability by:
- Evaluating the broader system performance, going beyond productivity by looking at profitability as well as sustainability indicators (e.g. soil N, SOC, GHG emissions, disease risk, microbiome diversity etc); and
- Testing ‘new’ yet-to-emerge systems for the first time.
Edillilie Site
Location: 5km north-east of Edillilie. Off Strawberry Hill Rd. -34° 23’02.26”S 135°45’37.65”
Farmer co-operator: Mark Modra
Rationale for the site selection
This site was considered to be of most interest to the largest cohort of growers on Lower EP. It represents a soil type that is more challenging to grow pulse crops on and has over the last 30 years grown a considerably high proportion of canola.
Average rainfall statistics: Annual rainfall: 522mm, April – October (426mm)
Soil description
Ironstone gravelly sandy loam over a brown clay grading to highly weathered kaolinized sediments.
Systems being evaluated:
| No. | System ID | Focus | Rotation | Tactical Treatments |
| 1 | Baseline | Canola-Wheat | 3 x N strategy:
STD – district practice Decile 2 - fertilise to decile 2 yield potential Decile 7 - fertilise to decile 7 yield potential |
|
| 2 | Diverse – high value | Include risky high value pulse crop | Lentil- Canola- Wheat-Wheat | 2 x N strategy:
Decile 2 - fertilise to decile 2 yield potential Decile 7 - fertilise to decile 7 yield potential |
| 3 | Diverse – low value | Include lower risk pulse crop | Faba Bean- Canola-
Wheat- Wheat |
1 x N strategy:
Decile 7 - fertilise to decile 7 yield potential |
Paddock History:
2022: Canola (Imi)
2021: Faba beans
2020: Wheat
Initial Soil Tests Results
Plant Available Water 29 March 2023: 0 mm
Mineral N 29 March 2023: 65kg/ha
Crops grown in 2023:
Wheat - Calibre
Canola – Nuseed Emu TF
Lentil – GIA Thunder
Faba beans – PBA Samira
Sowing date: 12 May 2023 – all crops. Canola delayed as paddock was canola in 2022 and wanted germination. That is why a short season cultivar is being grown.
Fertiliser @ sowing
Wheat: 100kg/ha DAP + Impact
Canola: 150kg/ha 19:13:0:9 + Impact
Pulses: 100kg/ha MAP
Nitrogen strategies
D2: Wheat and canola – 100kg/ha urea – target yield: 3t/ha wheat
STD: Wheat and canola – 200kg/ha urea – target yield: 4t/ha wheat
D7: Wheat and canola – 400kg/ha urea – target yield: 5.4 t/ha wheat
Comments on N Strategies: The N requirements were derived from yield potentials and N requirements relating to the various rainfall decile yields.
Yield Prophet: Output 14 August 2023
