One-off tillage options for water repellent gravel soils

CC BY 4.0

Research organisatons
Funding sources

Trial details

Researcher(s) Giacomo Betti (DAFWA)
Stephen Davies (DAFWA)
Liam Harte (DAFWA)
Year(s) 2015
Contributor West Midlands Group
Trial location(s) Dandaragan, WA
Moora, WA
One-off tillage options for water repellent gravel soils locations

To compare and assess the effectiveness of one-off tillage treatments on soil water repellence, water infiltration, crop establishment and productivity on a water repellent gravel.

Key messages

All tillage treatments had a little effect on the management of SWR and plant establishment in the severe water repellent gravel sand at Moora. Nevertheless, yield improvements were recorded, in particular with the “Large offsets” and the “Modified one-way with standard discs” treatments.

At this stage, it is not possible to clearly state what changes drove the yield increase. Given the little effect that the cultivations had on the SWR it is possible that improved soil structure, increased nutrient availability and nitrogen mineralisation may have played a role on the increased productivity.

The yield potential of the canola crop in 2015 was low given it was sown relatively late, plant numbers were low and there was a dry finish, this may have compromised the response to the tillage treatments. Observation of the trial in the following growing seasons and the response of a cereal crop in 2016 will help us to better understand the long term effect of the treatments on crop growth.

Lead research organisation Department of Agriculture and Food WA
Host research organisation West Midlands Group
Trial funding source DAFWA
Trial funding source GRDC DAW00224
Related program N/A

This work was supported by DAFWA and GRDC through DAW00244: ‘Delivering enhanced agronomic strategies for improved crop performance on water repellent soils in Western Australia’. Thanks and appreciation to Erin Cahill and Tony Snell for hosting the trial site, for one-way and offset ploughing and seeding the trial, and  to Ben and Sean Plozza for one-way ploughing. We acknowledge the technical support of Trevor Bell and Bruce Thorpe (DAFWA).

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


Crop type Canola
Treatment type(s)
  • Soil: Preparation
Trial type Experimental
Trial design Randomised,Replicated,Blocked

Dandaragan 2015

Sow rate or Target density 2.5kg/ha
Sowing machinery

The trial was established on April 2015 as a randomised block with three replicates of one control treatment and four different cultivation types: “Grizzly” large offsets; One-way plough; Modified one-way plough with either standard (‘shallow dish’) discs or ‘deep dish’ discs. The modified one-way disc plough had every second disc removed allowing more space for soil to turn and was fitted with larger discs to increase the working depth. In this experiment two disc types were tested with the modified one-way plough: 1) standard setup used ‘off-the-shelf’ large 76 cm (30 inch) discs which had a ‘dish depth’ of 115 mm and 2) a modified, more concave, disc was used which was built to have more curvature to promote greater turning of the soil, it had a diameter of 79 cm (31 inch) and a deeper dish depth.

Sow date 2 June 2015
Harvest date Not specified
Plot size 40m x 14m
Plot replication Not specified

Moora 2015

Sow rate or Target density Not specified
Sowing machinery Not specified
Sow date Not specified
Harvest date Not specified
Plot size Not specified
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
Dandaragan, WA Non-wetting sand
Moora, WA Not specified
Derived trial site soil information
Australian Soil Classification Source: ASRIS
Trial site Soil order
Dandaragan, WA Tenosol
Moora, WA Sodosol
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 Dandaragan WA Moora WA
2015 103.9mm321.4mm
2014 94.8mm341.2mm
2013 121.8mm404.2mm
2012 132.3mm416.7mm
2011 96.9mm361.1mm
2010 84.2mm378.8mm
2009 110.1mm372.9mm
2008 97.5mm399.7mm
2007 51.3mm390.1mm
2006 74.4mm430.0mm
2005 95.5mm368.1mm
2004 91.7mm357.8mm
2003 90.5mm382.9mm
2002 32.9mm362.3mm
2001 35.4mm359.6mm
2000 114.0mm469.2mm
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



Dandaragan WA 2015

Observed climate information

Rainfall trial gsr (mm) 299mm

Derived climate information

Dandaragan WA

Moora WA

Dandaragan WA


Moora WA


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: 06-08-2019 07:54am AEST