Investigating double break (or stacked rotation) options for weed and disease control

CC BY 4.0

Research organisaton
Funding source

Trial details

Researcher(s) Nathan Craig (WMG)
Brianna Hindle (WMG)
Chris Wilkins (WMG)
Year(s) 2017
Contributor West Midlands Group
Trial location(s) Merredin, WA
Related trials
Investigating double break (or stacked rotation) options for weed and disease control locations

To demonstrate the rotational benefits of a sequence of broadleaf, legume, and pasture crops for the production of wheat in the Kwinana West and East zones of WA.

Key messages

The trial will be going into its 3rd year in 2018 and all trial plots will be sown into wheat. The aim is to determine the difference in grain yield for wheat following a range of single or double break crop rotations, compared to continuous wheat. The site was established in 2016 on a paddock that had very high level of ryegrass that was affecting crop production. This area around this trial has been in pasture for 2017 as the comparison farmer solution for the issue.

Lead research organisation West Midlands Group
Host research organisation West Midlands Group
Trial funding source GRDC WMG00003-A
Related program N/A
Acknowledgments N/A
Other trial partners GRDC
Download the trial report to view additional trial information


Crop type Wheat
Treatment type(s)
  • Crop: Rotation
Trial type Experimental
Trial design Blocked

Merredin 2017

Sow rate or Target density 100 kg/ha
Sowing machinery

Kalyx seeder - knifepoint & presswheel 

Sow date 5 June 2017
Harvest date 25 November 2017 25th November 2017
Plot size 3.6m x 12m
Plot replication 4
Download the trial report to view additional method/treatment information

Download results

Trial results Table 1

# Variety
Treatment 1
Grain yield (t/ha)
1 Hurricane Lentils Merredin na
3 Field pea
4 Oats Merredin 0.78
5 Wheat Merredin 2.76
6 Jurien Lupin Merredin 2.72
8 Hurricane Lentils Miling 0.97
9 Wheat
10 Jurien Lupin Miling 0.82
12 Hurricane Lentils Miling 1.6
14 RR Canola Bencubbin 1.42
15 Jurien Lupin
16 Hurricane Lentils Bencubbin 0.59
17 Albus Lupins
19 Hurricane Lentils Bencubbin 0.6
20 Field pea Calingiri 0.97

Grain yield t/ha

Observed trial site soil information
Trial site soil testing
Site Depth Type pH EC P K N A OC CAT
Merredin, WA 0 - 10cm 4.70 0.17 22.00 54.00 0.57
Merredin, WA 10 - 20cm 4.60 0.05 19.00 36.00 0.27
Merredin, WA 20 - 30cm 5.60 0.04 7.00 30.00 0.17
Merredin, WA 30 - 40cm 6.00 0.04 3.00 26.00 0.14
Merredin, WA 40 - 50cm 6.20 0.08 2.00 47.00 0.15
Soil conditions
Trial site Soil texture
Merredin, WA Not specified
Derived trial site soil information
Australian Soil Classification Source: ASRIS
Trial site Soil order
Merredin, 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 Merredin WA
2017 291.2mm
2016 320.5mm
2015 301.9mm
2014 283.4mm
2013 334.1mm
2012 309.2mm
2011 274.5mm
2010 250.3mm
2009 281.9mm
2008 272.0mm
2007 246.8mm
2006 306.6mm
2005 274.8mm
2004 292.2mm
2003 295.6mm
2002 238.8mm
2001 286.1mm
2000 311.7mm
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



Merredin WA 2017

Observed climate information

Rainfall avg ann (mm) 328mm
Rainfall trial total (mm) 316mm
Rainfall trial gsr (mm) 195mm

Derived climate information

Merredin 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: 23-07-2019 14:57pm AEST