Comparison of pre-emergent herbicides for annual ryegrass control in wheat at four locations across WA in 2016


Research organisatons
Funding source

Trial details

Researcher(s) Rick Horbury (Bayer Crop Science)
Year(s) 2016
Contributor West Midlands Group
Trial location(s) Pithara, WA
Comparison of pre-emergent herbicides for annual ryegrass control in wheat at four locations across WA in 2016 locations

1.  Compare the efficacy of commercial pre-emergent herbicides and mixtures for ARG control across multiple soil types using grower machinery for seeding and ongoing management consistent with the grower’s practice.

2.  Determine yield and $ return on investment to the grower from current standard pre-emergent herbicides Sakura®, trifluralin, Avadex® Xtra and Boxer® Gold® with new options such as standalone prosulfocarb, the main component of Boxer Gold. Prosulfocarb (e.g. Arcade®) must be incorporated within 7 days of application.

Key messages

Over all four trials both Sakura treatments maintained a positive $ROI/ha with Sakura + trifluralin ($78.50) slightly ahead on average $ROI/ha to the standalone Sakura ($73.48)

Sakura 118 g/ha recorded a $55.08 increase in $ROI/ha over Boxer Gold across the four trials. Boxer Gold $ROI was generally in line with that of the prosulfocarb treatments in three of the sites, except from Waddy Forest where prosulfocarb 2.5 L/ha recorded a higher yield. Why this occurred is not clear as results were cross checked back with the contractor to ensure there was not a transcription error.

Trifluralin, due to its poor weed control, especially at Cunderdin, returned a slight positive $ROI/ha ($7.20) across the four trials.

All four sites to some extent were affected by frost which may have affected yield outcomes.

Getting weed control right is the key to ensuring the longevity of any herbicide but it also allows the crop it’s best possible chance of achieving its yield potential. Using a program of effective knockdowns and a product with a long residual activity like Sakura can deliver higher yields and returns across a variety of soil types and locations as seen across the four trials conducted during the 2016 season.


Lead research organisation Bayer CropScience
Host research organisation West Midlands Group
Trial funding source Bayer
Related program N/A

To the grower’s (Patton, McIlroy, Butcher and Syme families) that each hosted one of the trials, thank you for all your work in sowing and maintaining the sites and your understanding when hosting field walks. Thanks to Living Farm for the harvest of Waddy Forest, Pithara and Cunderdin, and DAFWA at Nugadong. To Michael Macpherson from Imtrade Australia, thanks for the use of your early season assessments and allowing your trial to be included in this multi-site review.

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


Crop type
Treatment type(s)
  • Herbicide
Trial type Experimental
Trial design Replicated

Pithara 2016

Sow rate or Target density 80kg/ha
Sowing machinery

Bourgault 8800 with Maxi knife points and press wheels. 

Sow date 19 May 2016
Harvest date Not specified
Plot size 2m x 30m
Plot replication 3
Fertiliser <p>100kg/ha Agras</p>
Herbicide <p>28 April: 1.1 kg/ha Ken Up dry 680 plus 100 mL/ha oxyfluorfen</p> <p>19 May: 3 L/ha paraquat</p> <p>&nbsp;</p>
Fungicide <p>670 mL/ha Velocity plus Uptake 0.5% v/v</p>
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
Pithara, WA Loamy gravel
Derived trial site soil information
Australian Soil Classification Source
Trial site Soil order
Pithara, WA 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



Pithara WA 2016

Observed climate information

Rainfall trial gsr (mm) 236mm

Derived climate information

Pithara 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.