Evaluating the potential for P replacement strategies

CC BY 4.0

Research organisaton
Funding source

Trial details

Researcher(s) Nicole Dimos (SPAA)
Chris Hunt (SPAA)
Michael Moodie (MSF)
Year(s) 2010
Contributor Society of Precision Agriculture Australia
Trial location(s) Mildura, VIC
Evaluating the potential for P replacement strategies locations

To use PA maps to indentify and sample soil zones within a paddock. To investigate soil phosphorus levels in different soil types with a paddock. To see if altering fertiliser rates at sowing has an impact on grain yield.

Key messages

There has been widespread use of continuous cereal in the Mallee over the past decade, and with many drought years throughout this period fertiliser inputs have generally been greater than crop demand. As a consequence, soil phosphoruslevels are often well above the critical level. By identifying soils and conditions where continuous cereal systems perform best and where inputs can be most effectively targeted, there is an opportunity to reduce input costs and increase profitability. This trial used PA methods to identify soil types for targeted soil sampling to achieve a greater understanding of soil phosphorus levels in different soil zones. Yield mapping was then used to identify if and where fertiliser applied to the crop impacted grain yield.

Lead research organisation Society of Precision Agriculture Australia
Host research organisation N/A
Trial funding source GRDC SPA000010
Related program N/A

Colin and Chris Hunt, Collaborating farmers, Mildura. Michael Moodie (Mallee Sustainable Farming)

Other trial partners Not specified
Download the trial report to view additional trial information


Crop type Wheat
Treatment type(s)
  • Fertiliser: Rate
  • Soil: Type
Trial type Precision agriculture
Trial design Not applicable

Mildura 2010

Sow rate or Target density 30 kg/ha
Sow date 20 May 2010 20 May 2010
Harvest date Not specified
Plot size Not specified
Plot replication Not specified


Download the trial report to view additional method/treatment information

Download results

Trial results Table 1

# Treatment 1
Sulphur (mg/kg) Electrical conductivity (dS/m) Soil ammonium (mg/kg) Plant available water (mm) Colwell phosphorus (mg/kg) pH CaCl2 (pH) Colwell potassium 0-10cm (mg/kg) Soil nitrate (mg/kg)
1 Dune 4.42 0.074 2 41 23 7.9 323 12
2 Swale 7.02 0.32 1 36 43 8.1 634 25

Colwell phosphorus mg/kg


Colwell potassium 0-10cm mg/kg


Electrical conductivity dS/m


pH CaCl2 pH


Plant available water mm


Soil ammonium mg/kg


Soil nitrate mg/kg


Sulphur mg/kg

Observed trial site soil information
Trial site soil testing
Not specified
Soil conditions
Trial site Soil texture
Mildura, VIC Brown sandy clay loam
Derived trial site soil information
Australian Soil Classification Source: ASRIS
Trial site Soil order
Mildura, VIC Calcarosol
Soil Moisture Source: BOM/ANU
Average amount of water stored in the soil profile during the year, estimated by the OzWALD model-data fusion system.
Year Mildura VIC
2010 254.2mm
2009 146.4mm
2008 98.3mm
2007 82.6mm
2006 122.3mm
2005 135.1mm
2004 145.3mm
2003 147.1mm
2002 143.9mm
2001 235.5mm
2000 272.5mm
National soil grid Source: CSIRO/TERN
NOTE: National Soil Grid data is aggregated information for background information on the wider area
Actual soil values can vary significantly in a small area and the trial soil tests are the most relevant data where available

Soil properties



Derived climate information

No observed climate data available for this trial.
Derived climate data is determined from trial site location and national weather sources.

Mildura VIC


Some data on this site is sourced from the Bureau of Meteorology

SILO weather estimates sourced from https://www.longpaddock.qld.gov.au/silo/
Jeffrey, S.J., Carter, J.O., Moodie, K.B. and Beswick, A.R. (2001). Using spatial interpolation to construct a comprehensive archive of Australian climate data , Environmental Modelling and Software, Vol 16/4, pp 309-330. DOI: 10.1016/S1364-8152(01)00008-1.

Trial last modified: 23-09-2019 17:21pm AEST