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A difference of opinion: glyphosate drift and formulations

With the Arkansas Plant Board considering new regulations to keep glyphosate-drift incidents to a minimum, concerns about product formulations are again being voiced.

Some agriculture leaders say any new spraying regulations should coincide with new, spray-friendly formulations.

Monsanto, the maker of various Roundup formulations used on Roundup Ready crops, insists its products are safe.

“When we put out a new formulation, we do a lot of testing which includes particle size,” says Zach Shappley, Monsanto Technology Development Representative, who works in Arkansas. “We’re confident that our formulations are safe when used according to label directions.”

When Shappley “or Extension weed specialists or someone else goes out and investigates a drift complaint, the majority of the time the applications aren’t made according to label directions. We have support on this from the academic community.” Shappley says he’s “unaware of any” state Extension weed specialist blaming glyphosate drift on formulation.

And Shappley has backers. Everyone agrees that improper application is the key cause of drift.

“If these proposed regulations become law and everyone must step up to the plate and get certified and attend a spray drift mitigation course and all that, there’s still a segment of agriculture that hasn’t been held accountable,” says George Tidwell, chairman of the Arkansas Plant Board. “That segment is the product manufacturer.”

Tidwell, the owner/operator of an aerial application service in Lonoke, Ark., says Monsanto plays “a big part in the problems with glyphosate. They’ll tell you it’s an applicator problem. But as an applicator that has been around a long time — as someone who runs a no-nonsense, first-class operation — I’m telling you that the formulation plays a role in drift.”

Pointing to a Roundup formulation called DPak, Tidwell says the company has had good formulations in the past.

“You could blow DPak towards rice and, in a reasonable wind, everything would be fine.

“Now, let me make this very clear: Monsanto has done us all a great favor and brought us a tremendous technology in Roundup Ready crops.

“But they’ve also given us a very poor tool to administer the Roundup program. Roundup can’t meet the droplet spectrum allowing it to be tank-mixed with Command.”

When developing a formulation, there are a set of spray properties Monsanto wants to achieve.

“Maybe a (formulation) contains droplets a bit smaller, but they’re still within a safe spectrum,” says Shappley. “There’s a minimum you don’t want to go under — you don’t want droplets smaller than that minimum. And none of our formulations approach that minimum.

“If you look at the data on our formulations sprayed alone, you won’t find anything that … would say, ‘That’s an unsafe product.’ I’m unaware of any data that says our formulations are unsafe. Roundup WeatherMax, Roundup OriginalMax sprayed (alone) provide appropriate droplet sizes.”

Still, many applicators feel strongly about current Roundup formulations and “I’m in their camp,” says Ford Baldwin, Arkansas weed scientist, consultant and Delta Farm Press contributor.

“There are major differences in the amount of fine droplets produced by different formulations. Roundup WeatherMax has failed to pass the droplet size test in a tank-mix with Command every time it’s been tested in Arkansas.

“There’s a lot of discussion on requiring droplet size studies on glyphosate in the future. Those would be very similar to what we’ve done with Command — if a formulation doesn’t pass a test, it won’t be registered.”

Because of vast acreage in its Roundup Ready crops, Monsanto swings a massive stick.

“The way its plays the replant game, a farmer is almost forced to use one of its products,” says Baldwin. “If the data shows its product is worse for fine droplets, it doesn’t matter. Farmers have no choice.”

Before crafting new glyphosate regulations (see, a task force on glyphosate drift was assembled. Bob Scott, Arkansas Extension weed specialist, was part of that effort.

While he says a different Roundup formulation would help decrease drift, the effect would be marginal without applicators ceasing to spray in unsafe conditions.

“The primary problem with Roundup drift is spraying when the wind is blowing too hard. It’s that simple,” says Scott. “Most of the rice drift complaints I walk — most, not all — are the result of poor judgment and spraying too close to rice in high wind.

“I do believe there are things that can be done with formulation to make it less prone to drift. But far more important are guys spraying when the wind is blowing too hard. No formulation change will stop Roundup from hurting rice if the wind is blowing 15 mph.”

And the number of drift complaints Scott receives from Roundup formulations is no greater than the number from other glyphosate products.

“Maybe what I’ve seen is outlier situations. I know a lot of people — people I respect very much — feel strongly that Monsanto could do some things to reduce drift potential.”

Baldwin is one of them. “Why not start out with the best formulation possible? That’s been our point all along. You know, Monsanto created Roundup Ready and it’s a miracle technology. But, as miraculous as it is, that means Monsanto is responsible for part of this problem. If the herbicides it’s requiring be used on its crop are prone to fine droplets, that’s a big part of this.”

Applicators have repeatedly asked for a Roundup formulation without surfactant.

“When you’re dealing with a pre-loaded product like many glyphosate formulations are — and glyphosate responds a bit more to surfactants than other herbicides — it’s more dangerous,” says Baldwin.

Tidwell would prefer a Roundup without surfactant. He’s confident in handling needed recipes.

“Let the applicator add the surfactant he deems best for his own operation and equipment configuration.”

Many crop and spray studies are conducted on Tidwell’s property.

“Specialists have been checking on getting approval for tank-mixes of OriginalMax and UltraMax with Command. It just won’t work because the droplet sizes are all wrong.”

Shappley says the tank-mix studies of Roundup WeatherMax and Command haven’t met minimum criteria. However, “that isn’t a labeled product. The people in Arkansas felt it was unsafe, FMC didn’t like it, and so there’s no label. And that’s fine. It’s not a big deal for us.

“But the things that are labeled with our products, when sprayed according to label directions, are safe.

“We could come out with a formulation that makes big, huge droplets. We could spend millions of dollars to do that. But will that really change the (drift) issue in Arkansas? We don’t believe it would.

“Theoretically, we could come out with a ‘low-drift’ or ‘no-drift’ formulation. But that would just exacerbate the problem. It would just provide a false comfort level — ‘this isn’t going to drift anywhere so I can spray it anytime I want.’”

Tidwell says the drift/formulation confluence is “a very serious problem. The applicator insurance companies cannot continue to pick up the tab for Monsanto’s refusal to change a product that isn’t user-friendly. No product should produce droplet sizes so small they’ll travel a couple of miles and damage green-ring rice.”

Applicators, says Tidwell, have improved their technologies and equipment — both ground and air.

“At great expense, we’ve brought our industry into a new technological age. But even with all that we can’t control the chief glyphosate product, one we’re compelled to use.”

What will lessen drift incidents is education and enforcement, says Shappley. “Those are the two places where we want to put our money. We want to be part of the education process in whatever capacity we can. And we’ve communicated that to everyone — the drift task force, the Plant Board. We want to be a part of education because that’s where our dollars really make a difference.”

Asked about new technologies, Shappley says Monsanto’s future plans “include dicamba-tolerant soybeans and cotton. Those will be launched several years down the road. With those coming, we realize a potential issue that could come up … is drift. So, as part of our overall plan to bring that technology to the marketplace, we’re looking at things like dicamba formulations, drift mitigation and other strategies. We are addressing ways where that product can be launched and used in a safe environment.”

Tidwell is all for education.

“Yes, we should all be educated and studying from the same textbook if we’re to apply pesticides. But that doesn’t mean the chemical manufacturers don’t have a dog in the drift hunt.”


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