Long term tillage and rotation trial


Research organisaton
Funding source

Trial details

Researcher(s) Barry Haskins, Rachael Whitworth (AgGrow) and John Small (CWFS)
Year(s) 2016
Contributor Central West Farming Systems
Trial location(s) Merriwagga, NSW
Long term tillage and rotation trial locations

To evaluate the productivity and profitability of no-till farming techniques against conventional farming
methods under various cropping rotations.

Key messages
  • After 18 years there was no standout rotation, in terms of profitability, in any given season. All  rotations had their pros and cons in both wet and dry years. Therefore having a mix
    of rotations and doing things on time is a recipe for a resilient business.
  • The most profitable rotation for the duration of the trial was the continuous cropping rotation, which included two wheat crops followed by a pulse crop in a no-till system. The addition of the pulse crop every third year was beneficial, especially for adding extra nitrogen, however added issues such as broadleaf weed blowouts with weeds like fumitory.
Lead research organisation Central West Farming Systems
Host research organisation N/A
Trial funding source GRDC CWF00018
Related program N/A
  • Ag Grow Agronomy and Research and Central West Farming Systems would like to acknowledge Ian Barber “Sylvanham” for undertaking various activities such as sowing and harvesting the trial, as well as other local farmers in their efforts to help make this trial what it is.
  • This trial in effect has been unfunded for the majority of its duration, with exception of part of the funding for the 2014- 2016 activities coming from the GRDC project CWF00018 ‘Maintaining profitable farming systems with retained stubble in Central West NSW’.
  • Thanks to all the fun times looking after this trial with innovative growers over the years

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


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

Merriwagga 2016

Sow date Not specified
Harvest date Not specified
Plot size 300m x 33.3m
Plot replication Not specified
Download the trial report to view additional method/treatment information

Trial results Table 1

# Treatment 1
Treatment 2
Grain yield (kg/ha) Gross margin ($/ha) Total variable costs ($/ha)
1 Continuous wheat Conventional 3089 209.34 331.29
2 Continuous wheat No till 3038 249.96 281.75
3 Rotation 1 Conventional 3524 291.36 331.29
4 Rotation 1 No till 2924 276.44 281.75
5 Rotation 2 Conventional 4349 437.31 331.29
6 Rotation 2 No till 4329 475.94 281.75
7 WLFW Conventional - -57.21 57.21
8 WLFW No till - -57.21 57.21
9 WFW Conventional 4193 341.76 331.29
10 WFW No till 3684 336.58 281.75

Grain yield kg/ha


Gross margin $/ha


Total variable costs $/ha

Observed trial site soil information
Trial site soil testing
Not specified
Soil conditions
Trial site Soil texture
Merriwagga, NSW Not specified
Derived trial site soil information
Australian Soil Classification Source
Trial site Soil order
Merriwagga, NSW Kandosol
National soil grid Source
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.

Merriwagga NSW


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

2016 trial report