Adjuvant Industry Could Face Regulatory Dilemma

There is a catch to the long-awaited approvals of the new technologies from Dow AgroSciences, Monsanto, and BASF, and it’s a big one.


Any tank mix partner must pass the EPA-approved protocol, and that means wind-tunnel testing and data gathering for each of the new cropping systems. As growers seek to make as few passes as possible across the field to save money and time, they will likely want to put more products into their tank than say, the 2,4-D-based Enlist Duo chemistry, alone.

Yet, there are literally endless combinations of products — not only adjuvants, but active ingredients — that could be tank-mixed with the new technologies. Aside from not having enough time in our lifetimes to test them all, the companies recommend testing protocol that are inconsistent with each other.

Most likely, a reasonable solution will win out, but regulatory bottlenecking before that happens remains a potential problem, says Adam Arellano, Product Manager with Loveland Products. “I am optimistic that EPA and the industry will come to a fair way of figuring how to test things and make sure they are safe and in accordance with what EPA needs as well as what makes practical sense for growers and applicators to go out there and have a productive crop. So I’m optimistic, but it’s definitely an anxious time as well,” he says.

John Combest, Monsanto spokesman, says, “While EPA has yet to issue its draft decision — which will include a draft label — for dicamba herbicide over the top of Roundup Ready 2 Xtend soybeans, we anticipate that some drift reduction agents will be approved for use. Those EPA labels will also likely be specific about other adjuvants required or forbidden.”

Related to all of this is the issue of nozzles. The first dicamba labels are expected to strictly limit what applicators can use, Dr. Bob Wolf, application specialist and consultant, explains.

“BASF and Monsanto are going to be limited to one nozzle design, and that’s the TeeJet TTI,” he says, pointing out the concern that if the nozzle is not used correctly it may not always be the best for getting coverage and attacking hard-to-kill and resistant weeds. For Dow’s Enlist Duo, the label that has been made available will have several nozzle options, each with specific pressure restrictions to manipulate the droplet size needed for that product.

Bob Wolf adds: “We’re talking about dicamba and 2,4-D. Those have a history in the ag market of drift problems. EPA is cautious of that and doing an extensive data review.”

Further complicating the environment is EPA’s AGDISP system, which crunches the numbers to determine the buffer zone needed for a given product or product combination. The AGDISP modeling system was developed for aerial applications, yet the Big 3’s new technologies are all ground applications. Dow has done work that shows the modeling system’s calculations do not always translate correctly to ground applications.

The question is, who fixes the system, and how? Council of Producers & Distributors of Agrotechnology (CPDA) has worked to get it fixed, but EPA lacks the funds to implement changes.

On top of all of this, EPA’s heavily debated new star-rating system enters the picture. This system rates drift reduction, and it relies heavily on nozzles to do so. In essence, this simplifies matters but is not entirely accurate. This is largely because nozzles that reduce drift tend to increase droplet sizes, but do not necessarily facilitate good coverage, which could lead to more spraying if the desired effect isn’t achieved on the first pass.

The star-rating system is voluntary, but since it ultimately affects buffer zones, it can in effect potentially limit a company’s market share.

As Arellano points out, the key is finding a balance between performance and drift control. “There’s a lot of products out there that can have a really good drift rating, but are they the best products to use in every situation? A garden hose doesn’t create a lot of drift, but it might not be what I want to be using,” he says. “Our existence is to try to find solutions to maximize performance and find that balance of being responsible from an environmental and product stewardship standpoint, but also give growers tools that are going to be practical to help their crop.”

How growers will ultimately weigh the different factors involved and decide what to spray, or who to hire to advise them what to spray, is anyone’s guess. One possible worst-case scenario is that rules will be broken because they’re so complicated. At the end of the day, the growers need to go after their resistant weeds.

Dr. Greg Kruger, Assistant Professor and Cropping Systems Specialist at the University of Nebraska-Lincoln, says the impact of the star-rating system will not be felt much — yet.

“Over the long term, it could potentially have a huge effect on how we approach applications, how we develop products, and what we’re looking for in terms of developments. I don’t think it’s going to change a lot in the next year.”