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Is sunlight breaking down herbicides for dry sowing?

Is sunlight breaking down pre-em herbicides where farmers are dry sowing? Our Western Extension Agronomist, Peter Newman, has been fielding questions over the last few days via Twitter on this. He did some digging and found that sunlight is only having a small effect on pre-emergent herbicide degradation. It turns out that light rain is the main risk – firing up microorganisms to start microbial degradation before the true season break.

ICAN’s Mark Congreve, AHRI’s Dr Roberto Busi and University of Adelaide’s Dr Christopher Preston provided Pete with some more detailed information which he has put together to explain what’s happening in the video below.

We’ve also made Module 4 from our latest Diversity Era Course, Pre-Emergent Herbicides 101, with Dr Christopher Preston, available. You can watch the video below where Chris talks in detail about herbicide breakdown. Did you know you can do all of our Diversity Era courses for free? You can sign up for Pre-Emergent Herbicides 101 here.





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