Today’s column is in the form of a two-part story. Hopefully it will demonstrate the danger in not thinking long-term and trying to identify the unintended consequences when making farming decisions. Before we start, the goal here is not to identify villains, or heroes for that matter, but the need for everyone involved in agriculture to try and think in the very long-term and critically evaluate information. And for those of us past a certain age, this is the Readers’ Digest version.
By the late 1980s broadleaf weeds were developing resistance to the herbicide chemistries used to control them in soybean fields. Companies like Monsanto and DuPont were working on a solution. Both came up with a solution at approximately the same time. Monsanto through the magic of genetic engineering developed Roundup Ready ® technology that allowed this nonselective herbicide to spray over soybeans without harming, provided you followed directions, or killing them. Glyphosate, the active ingredient in Roundup, completely controlled not only troublesome broadleaf weeds in the soybean crop but also most grasses. And Monsanto promoted this as a way to eliminate pre-plant/emergence spraying with more expensive chemistries. To further help producers decide, Monsanto also dramatically slashed the price of Roundup.
DuPont developed STS technology to address the same issue at the same time. STS stands for sulfonylurea tolerant soybeans. This was a different mode of action from Roundup and involved several herbicides that were particularly effective at control but also at damaging/killing soybean plants and STS technology overcame that problem. An additional advantage was that these chemistries had residual activity while Roundup didn’t. They also looked at soybeans that were both Roundup and STS tolerant but didn’t release them then. They didn’t dramatically cut the price of their products nor did they promote it as being able to eliminate pre herbicide programs. They didn’t emphasize cheap control as much as good, sustained control.
Weed control scientists and extension specialists in the corn and soybean growing regions of the country weighed in with concerns. They stressed the need for pre-emergence herbicides for early season control. They had other concerns, especially the need to rotate modes of action (what kills the weed) but here was their major fear. Roundup had been around for almost twenty years by then and was used to control weeds in place of tillage. For example, Kansas wheat farmers used huge quantities of it for fallow weed control to conserve soil moisture. One of the benefits of rotating crops between grasses and broadleaves was you rotated herbicide mode of action. The mantra was to really control your grasses in the broadleaf crop and the broadleaf weeds in your grass crop. They liked what this technology did but that it needed to be used as part of an integrated herbicide program, not as a standalone. Based upon what had happened with early herbicides for corn and soybeans, they were afraid the overreliance on a single mode of action would create herbicide resistance in problem weeds that were already resistant to other herbicides.
As you probably know, cheap and easy Roundup won the day. It was not only cheap but it worked great after a few bugs were worked out and as the technology allowed for spraying over a longer time window. DuPont’s STS technology, which worked as good as or better than Monsanto’s didn’t fare well and within a few years Roundup Ready ® soybeans ruled the market. Next week: what happened and most of us don’t really know the whole story.

Dr. Victor L. Martin is the agriculture instructor/coordinator for Barton Community College. He can be reached at 620-792-9207, ext. 207.