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New online course de-mystifies pre-em herbicide use

The herbicide-only era is over and the diversity era is here. One example is coupling pre-emergent herbicides with greater crop competition.

In a brand new, free online course taught by Dr Chris Preston (University of Adelaide) and Mr Mark Congreve (ICAN), growers and agronomists can gain confidence through understanding how to best use pre-emergent herbicides in both winter and summer cropping systems.

Mark Congreve (ICAN), Chris Preston (University of Adelaide) and Peter Newman (AHRI) discuss the ins and outs of pre-emergent herbicide in Australian cropping systems in a new Diversity Era online course.

The Diversity Era Pre-emergent Herbicides 101 course includes:

  • free access to 13 educational videos that cover the basics of how pre-emergent herbicides work, plus practical tips to help you use these herbicides on farm in both summer and winter cropping systems
  • straightforward, step-by-step instruction from highly respected and skilled industry professionals with deep knowledge of cropping systems and weed management
  • access to a comprehensive overview of what is currently known about pre-emergent herbicides and how to best use them in your farming system
  • Q&A discussion with Chris and Mark (facilitated by Peter Newman), a resource library with extra information, podcast interviews and a live webinar.

In just three hours, find out how pre-emergents can help manage herbicide resistance in crop weeds. There’s videos, audio, PDF downloads, quizzes and a wrap-up webinar to help you get the most out of the Diversity Era Pre-emergent Herbicides 101 course, while working at your own pace.

Given that pre-emergent herbicides require more planning and carry some inherent risks, it is important to understand how they work in different soils, how they can be used most effectively through a cropping program, including the fallow, and how to manage any restrictions on future crop choices.

Dr Chris Preston says that the renewed interest in adding pre-emergent herbicides to weed control programs is in response to the rapid escalation in herbicide resistance to post-emergent herbicides and the important knockdown herbicide, glyphosate.

“Currently, the only widely used herbicide mode of action group in Australian grain production that has no known field populations of herbicide resistant weed species is Group H,” he says. “Pre-emergent herbicides are also prone to herbicide resistance, with the number of resistant populations on the rise, so their judicious use is essential. Incorporating pre-emergent herbicides into the program increases the diversity of herbicide mode of action groups, making it possible to mix and rotate these herbicides to extend their effective life. A well-executed pre-emergent program can also take the pressure off subsequent post-emergent in-crop herbicide applications.”

“Knowing how to maximise efficacy and stack these products with other tactics, such as crop competition, harvest weed seed control and stopping weed seed set, needs to be part of the crop management package on every farm, every year.”

Having presented innumerable pre-emergent herbicide use workshops around Australia and co-authored practical information resources for agronomic advisors, Mark Congreve is keen to see all growers and advisors familiar with the soil behaviour of pre-emergent herbicides.

“Understanding the risks and benefits associated with these herbicides is very important,” he says. “This course is a great refresher and a resource that growers and agronomists can refer back to over and over again as they integrate pre-emergents into their weed management program to suit each season and crop sequence in both winter and summer cropping situations.”

The Diversity Era Pre-emergent Herbicides 101 course opened for registration on 20 March 2019, with the release of the first five modules – ‘Understanding Pre-em Basics’ with Chris Preston and a podcast with Chris and AHRI’s Peter Newman.

Modules 6–8 ‘Using Pre-ems in a Winter Cropping System’ with Chris will go live on Wednesday 27 March and Modules 9–11 ‘Using Pre-ems in a Summer Cropping System’ with Mark Congreve will be available the next week on 3 April, along with two bonus materials modules and another podcast, this time with Mark and Peter. The final element will be a live webinar on April 10 with Peter Newman, Mark Congreve and Chris Preston.

Register now: www.diversityera.com/courses/pre-emergent-herbicides-101

Initiatives like our latest Diversity Era course ‘Pre-emergent Herbicides 101’ (which is free!) are made possible through the support of our stakeholders. Please watch the above video highlighting stakeholder engagement to learn more.

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