Variable rate nitrogen

CC BY 4.0

Research organisaton
Funding source

Trial details

Researcher(s) Nicole Dimos (SPAA)
Neil McMillan (Central West PA)
Year(s) 2010
Contributor Society of Precision Agriculture Australia
Trial location(s) Nyngan, NSW
Variable rate nitrogen locations
  • To compare the variability of nitrogen needs across a paddock of canola
  • To try and develop a method of assessing when and how much Nitrogen to apply.
Key messages

The objective of this GRDC / SPAA funded project is to increase the level of adoption of PA 'beyond guidance' by broadacre farmers. The project specifically aims to increase the level of adoption of variable rate (VR) by growers in the project to 30% by 2013.This goal will be achieved by demonstrating how to use PA tools to growers at a regional level and by increasing the skills of growers and industry in PA to a level where they can then use PA tools in their farming systems to achieve economic, environmental and social benefits.

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

Neil McMillan - CWFS, Leighton Wilksch - SPAA, James Austin - gps-Ag, Ian Packer - Lachlan CMA. The project was funded by the GRDC

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


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

Nyngan 2010

Sow rate or Target density 1.55kg/ha
Sow date Not specified
Harvest date 8 November 2010 8 November 2010
Plot size Not specified
Plot replication Not specified

N rich strips applied at 200kg/ha on the 18th of April.

Download the trial report to view additional method/treatment information

Download results

Trial results Table 1

# Treatment 1
Soil nitrate (mg/kg) pH CaCl2 (pH) Colwell phosphorus (mg/kg) Organic carbon 0-10cm (%)
1 Low - Zone 1 2.8 5 43 0.64
2 Low - Zone 1 3 5.8 16 0.59
3 Low - Zone 1 4.4 5 20 0.57
4 Medium - Zone 2 2.1 5.1 16 0.57
5 Medium - Zone 2 1.8 5.4 14 0.58
6 Medium - Zone 2 1.9 5.6 13 0.58
7 High - Zone 3 3.8 5 36 0.68
8 High - Zone 3 5.6 5.5 33 0.95
9 High - Zone 3 8.5 5.1 31 0.69

Colwell phosphorus mg/kg


Organic carbon 0-10cm %


pH CaCl2 pH


Soil nitrate mg/kg

Observed trial site soil information
Trial site soil testing
Not specified
Soil conditions
Trial site Soil texture
Nyngan, NSW Heavy mottled clay
Derived trial site soil information
Australian Soil Classification Source: ASRIS
Trial site Soil order
Nyngan, NSW Vertosol
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 Nyngan NSW
2010 430.7mm
2009 373.6mm
2008 336.5mm
2007 236.0mm
2006 245.5mm
2005 290.8mm
2004 281.2mm
2003 294.9mm
2002 327.4mm
2001 414.9mm
2000 459.0mm
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.

Nyngan NSW

NOTE: Exact trial site locality unknown - Climate data may not be accurate

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

SILO weather estimates sourced from
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: 30-09-2019 16:09pm AEST