Switching gears. Diversity is not just important for cover crops and rotations, but also for herbicides, says Bryan Young, professor of weed science at Purdue University. Young says no-tillers should diversify their toolbox for weed management because as he tells us here, some of our current herbicides might not even work in a few years. 

“I think by the end of this decade, there's a good chance there'll be some fields where the oxygen herbicides and glufosinate liberty don't work anymore on important species like palmer amaranth and waterhemp. I think that's pretty easily said because in some fields we already have one or maybe two of those herbicides that have stopped working. So now we're just relying on the other one, the third one to take us home the rest of the way. And I don't think it's going to last for six years. We don't have that much time, even if we practice good crop rotation and only apply it three more times. But there's a lot of herbicides we apply in our corn that we're also applying our soybeans today. And that's the other thing that we've done is if a herbicide worked in corn, we decided, well, why don't we use that in soybeans as another tool? So that's where we really aren't rotating away from some herbicides like we used to be able to when we had, let's just say non-GMO crops, pre 1996 after herbicide resistant crops, that's when we enabled a lot of herbicides to be used in corn and beans because they're good and effective. And why not use them well, it contributed a little bit towards herbicide resistance. Evolution is a good reason why we should not have.”

Young says a good place to start is by focusing on rotating post-emergent herbicides from year to year. 

Watch the full version of this episode of Conservation Ag Update.