Where has all the phosphorous gone?

CC BY 4.0

Research organisaton
Funding sources

Trial details

Researcher(s) Bill Bowden (West Midlands Group)
Criag Scanlan (DAFWA)
Year(s) 2014
Contributor West Midlands Group
Trial location(s) Badgingarra, WA
Where has all the phosphorous gone? locations

To characterise the residual value of different P sources and changes in soil fertility (SOC, CEC, pH, nutrient supply, non-wetting, compaction) after 30 plus years, using soil measurements and bioassay cropping.

Key messages

30 years after application, water soluble P leaches to depth on grey sands but is still effective for the growth of deep rooted blue lupins.  On the one-hand, the citrate-soluble P in C-500 releases more slowly through time and so has a longer term residual effect than water soluble P. On the other hand, higher rates of C-500 are required than superphosphate to reach maximum yield when soil P levels are low.  It is less likely to leach and so pollute ground waters. If cheap enough, C-500 could be used as a maintenance P fertiliser.  Much work is still to be done on this trial site.

Lead research organisation West Midlands Group
Host research organisation N/A
Trial funding source NACC
Trial funding source DAFWA
Related program N/A

Thanks go to the 1980 instigators of the trial: Mike Baker and, Mike Bolland to the landowners, David Frankland, Geoff Pearson, to the funders, NACC, and to the sponsors, the West Midlands Group and DAFWA.

Other trial partners DAFWA
Download the trial report to view additional trial information


Crop type No crop specified
Treatment type(s)
  • Soil
Trial type Experimental
Trial design Replicated

Badgingarra 2014

Sow date Not specified
Harvest date Not specified
Plot size 60m x 3m
Plot replication Not specified
Download the trial report to view additional method/treatment information
Trial source data and summary not available
Check the trial report PDF for trial results.
Observed trial site soil information
Trial site soil testing
Not specified
Soil conditions
Trial site Soil texture
Badgingarra, WA Not specified
Derived trial site soil information
Australian Soil Classification Source: ASRIS
Trial site Soil order
Badgingarra, WA Chromosol
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 Badgingarra WA
2014 226.8mm
2013 251.5mm
2012 236.0mm
2011 224.8mm
2010 209.6mm
2009 228.5mm
2008 246.8mm
2007 198.9mm
2006 196.0mm
2005 242.6mm
2004 204.2mm
2003 230.9mm
2002 212.7mm
2001 192.5mm
2000 206.7mm
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.

Badgingarra WA

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 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 report and links

2014 trial report

Trial last modified: 23-07-2019 11:48am AEST