Current Project

CRDC Benchmarking the Costs and Benefits of Defoliation Strategies

This project in conjunction with Bill Gordon Consulting consists of a survey of industry practices and a field trial comparing ground and aerial defoliation parameters.

Recent Projects

CRDC Developing an Industry Agreed Strategy for Managing Herbicide Resistance in Cotton.

This was an extension project to develop a herbicide resistance management strategy (HRMS) in conjunction with industry stakeholders and approved by industry bodies. The cotton HRMS was developed over a period of eleven months and launched at the 2014 Australian Cotton Conference in August. The HRMS can be found in the 2014/14 Cotton Pest Management Guide.

Weed control efficacy in standing stubble

A large scale trial for Bill Gordon Consulting as part of a GRDC project. The aim of the trial was to determine whether distance from the spray rig wheel track affected droplet deposition and weed control efficacy with glyphosate in standing cereal stubble. Three nozzle types and two application speeds were evaluated. Statistical analysis showed significant differences in barnyard grass control resulted depending on distance from the wheel track, nozzle type used and speed of application. Interactions between these factors also resulted in significant differences in weed control.


Bill Gordon Consulting has been conducting and contracting efficacy based trials on behalf of R&D Corporations and product manufacturers for over a decade. In that time I have worked with a number of contract research organisations and grower groups throughout Australia.

In 2014 I contracted AGDel to complete an efficacy based trial designed to assess the impacts of travel speed and spray quality on efficacy in standing stubble at several locations across a self-propelled sprayer, with the aim to replicate commercial practices for knockdown herbicide use in fallow situations.

This trial required that treatments be applied using commercial spray equipment and at a range of spraying speeds (one at 27 km/h). The assessments required efficacy to be assessed predominantly in the standing stubble, and in a number of locations relative to the wind direction and the direction of travel of the sprayer.

Annabelle Guest provided great assistance and feedback during the design and analysis phase. All of the field work was completed as per agreed timelines, with excellent feedback along the way. The comprehensive report, including a thorough analysis of the data received at the conclusion of the trial was of a high standard.

I think I can honestly say that this is the first time in over a decade of contracting efficacy based field trials that I have been completely satisfied with the way in which the trial has conducted and reported on my behalf.

I would happily recommend AGDel to other organisations looking for contract research services.

Drift control adjuvant tested with herbicide in fallow

AGDel is one of the first commercial operators in Australia to work with the new Caltex drift reduction product 'Dead Sure' which has been shown to dramatically mitigate spray drift (by up to 70%) while enhancing fallow herbicide efficacy when using low drift Teejet nozzles.

A trial was conducted against fleabane, barnyard grass and liverseed grass - which are considered three of the harder to control summer fallow weeds. The trial evaluated Dead Sure applied with glyphosate through different nozzles Teejet TTI, TTJ60 AITTJ60 and AIXR nozzles.

The evaluation involved a “double knock” trial using Dead Sure applied with glyphosate followed by Dead Sure applied with Paraquat as a double knock.

This trial was a double knock scenario with 19 treatments and three replications. Statistical analysis using ANOVA was conducted and means separated using LSD’s. A report for an APVMA submission was then produced.

Cotton Defoliation

A project involving four large scale product evaluation trials is currently underway. The trials are being conducted in the Namoi Valley of northern New South Wales and in the Riverina region of southern NSW using both aerial and ground application equipment. Bryce and Annabelle have worked together in the application and management of the Namoi trials and Annabelle is project managing the Riverina trials and has personally conducted all assessments.