Ongoing yield responses to amelioration of water repellent sand 3 years after treatment

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Research organisatons
Funding source

Trial details

Researcher(s) Stephanie Boyce (DAFWA)
Stephen Davies (DAFWA)
James Hagan (DAFWA)
Year(s) 2013
Contributor West Midlands Group
Trial location(s) Badgingarra, WA
Ongoing yield responses to amelioration of water repellent sand 3 years after treatment locations

To assess amelioration options for water repellent soil and to determine whether a one-way plough can be used to ameliorate non-wetting sand for much lower cost than mouldboard ploughing or rotary spading.

Key messages
  • Average grain yield for the untreated control plots was 2.34 t/ha. Clay spreading and rotary spading gave the largest machine harvest grain yield responses of 400 kg/ha or more, mouldboard ploughing 270 kg/ha and one-way ploughing 180 kg/ha (Figure 1) compared to their nearest comparative control plots. Offset discs gave no yield response in 2013 but did have positive yield responses in previous seasons (Table 1).
  • Grain protein levels averaged 11.4% for the untreated controls, clay spreading had 0.5% more protein and mouldboard ploughing 0.2% than their neighbouring controls (data not shown).
  • Screenings for the majority of treatments averaged about 2.1%. Mouldboard ploughing was the only treatment to have significantly lower screenings of just 1.2% (data not shown).
  • Total above-ground shoot biomass and head number was assessed using plant cuts (Table 1). Shoot biomass on average was increased by 95% (+4.3 t/ha) by rotary spading, 57% (+2.7 t/ha) by clay spreading and 47% (+2.3 t/ha) by mouldboard ploughing compared to the untreated controls. Head numbers on average were increased by 32% (78 heads) by spading, 22% (58 heads) by mouldboard ploughing and 17% (43 heads) by claying compared to the untreated controls.
  • Observations made earlier in the season indicated that emergence of many plants in the untreated control areas was delayed and had fewer tillers than the earlier emerging plants in the many of the treated areas.
  • The whole plant cut transects were taken across different soil types, rotary spading gave the best results on the poor pale deep sand at this site while mouldboard ploughing performed best on the better yellow sand (Transect 3).
  • The net 3-year benefit and return on investment (ROI) has been determined for the first 3-years of the trial (Table 2). Estimated costs for the amelioration treatments are based on owner-operated and contract rates. Benefits associated with some of the treatments such as weed control for the mouldboard plough and reduced wind erosion for the claying treatment have not been included.
  • The one-way ploughing treatment was the most affected by wind erosion in 2011, resulting in a loss in grain yield and income which has substantially reduced the net benefit and the return on investment for this treatment although the subsequent years have been profitable (Table 2). Of the other treatments rotary spading and mouldboard ploughing had the highest net benefit, driven largely by the large lupin yield increases measured in 2012. Claying also had impressive yield gains and substantial increases in income (Table 2) but the high cost of this treatment reduced the 3-year net benefit and return on investment relative to the deep cultivation treatments. Given that claying can show benefits for decades net benefit and ROI for this treatment should continue to improve over time and it still only took 2 years to cover the cost of the treatment. Offset discs had grain yield benefits for the first 2 years but showed no response in 2013 suggesting that the benefits of the shallow cultivation may have dissipated.
Lead research organisation Department of Agriculture and Food WA
Host research organisation West Midlands Group
Trial funding source GRDC DAW00204
Related program Delivering agronomic strategies for water repellent soils in WA

Particular thanks to Colin ‘Ferret’ McAlpine for establishing the trial with the assistance of David Hayes and Craig White. Research funded by DAFWA & GRDC through the “Delivering agronomic strategies for water repellent soils in WA – DAW00204” project and by the West Midlands Group.

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


Crop type Wheat
Treatment type(s)
  • Soil amelioration
Trial type Experimental
Trial design Replicated

Badgingarra 2013

Sow rate or Target density 90 kg/ha
Sow date 10 June 2013
Harvest date Not specified
Plot size 9m x 190m
Plot replication Not specified

120 kg/ha MacroPro Trace and 40L Flexi-N down tube at seeding; 80 kg/ha NS51 post-seeding.

Soil amelioration

1)    Control - untreated

2)    Mouldboard ploughing to ~35 cm,  April 2011

3)    Clay-spreading, 120 t clay-rich subsoil/ha, April 2011, shallow (10 cm) incorporation

4)    Rotary spaded to ~35 cm, April 2010

5)    Offset discs to ~10 cm, April 2011

6)    One-way disc plough to ~15 cm, April 2011

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 Pale deep sand
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
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



Badgingarra WA 2013

Observed climate information

Rainfall trial gsr (mm) 446mm

Derived climate information

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
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: 10-07-2019 13:21pm AEST