What exactly is Dow AgroSciences promising in its reinvention of 2,4-D herbicide, application technology and crop tolerance under the Enlist Weed Control System name?

The new Enlist system is a herbicide-tolerant trait technology that comprises three components: Enlist traits, Enlist Duo herbicide and Enlist Ahead management resource. Pending regulatory approvals, the system will be introduced for corn production in 2013, for soybean production in 2015 and cotton production in 2016.

“Enlist Duo will provide a proprietary blend of new 2,4-D choline and glyphosate and will control glyphosate-resistant and tough-to-control weeds. It features Colex-D Technology, a proprietary manufacturing process and novel formulation science, for the new 2,4-D choline,” said Mark Peterson, Dow AgroSciences, global biology leader for the Enlist system.

“We developed Colex-D Technology to address concerns associated with off-target movement, odor and handling. Enlist Duo with Colex-D Technology will provide user benefits through these advancements,” he added.


“The 2011 results reconfirmed the volatility reduction that had been found in previous trials. These volatility trials compared the new 2,4-D choline, available in the Enlist herbicide solution with Colex-D Technology, to traditional forms of 2,4-D now on the market. The result: the new 2,4-D choline showed a 92 percent reduction compared with a traditional form of 2,4-D. This measurement was taken 60 hours after herbicide applications,” Peterson said.

Numerous universities have also conducted in-field research trials. Dan Reynolds, a Mississippi State University weed scientist, concluded 2,4-D choline reduces the drift plume significantly compared with glyphosate tank mixes with traditional  2,4-D.

Colex-D Technology also provides advancements with lower odor and better handling characteristics also confirmed by third-party trials.

Peterson noted, “In studies, herbicides with Colex-D Technology were compared with a tank mix of glyphosate and traditional 2,4-D. The research shows Colex-D Technology reduced physical drift by 45 percent with the formulation improvements alone.

Enlist Weed Control System“This decrease in drift comes from the Colex-D Technology that was created to reduce the production of driftable fines without a significant increase in the relative droplet size. Finding the right droplet size is vital for herbicide efficacy. Too big, it might not stay on the intended weed. Too small, it might drift before it lands.”

The graph with this article illustrates the reduction in the percent of driftable fines in the spray solution from 51.1 percent for the tank mix compared with 18.8 percent for Enlist herbicide solution sprayed with the same nozzle and pressure. “This shows that the new herbicide will provide applications with the ideal droplet size and fewer driftable fines,” Peterson said.

He also explained that herbicides with Colex-D Technology show even further reduction in physical drift when combined with a low-drift nozzle, such as an AIXR tip. The new herbicide combined with the nozzle reduced drift up to 90 percent in the comparison trials.


To ensure growers and applicators have “the resources to use the new Enlist Weed Control System,” Dow AgroSciences has created Enlist Ahead. It is a “management resource” designed to help farmers succeed while promoting responsible use of the Enlist system. Although the company prefers not to call it a stewardship program, because it claims it is much more, that is the best comparison.

The resource is built on three pillars—technology advancements; education, tools and training; and management recommendations. All those are important to ensure the Enlist system is used wisely. Various groups have expressed concern that there will not be enough stewardship of the system and traditional 2,4-D products will be used by farmers not concerned enough about drift onto their neighbors’ crops.

With that in mind, Dow AgroSciences has been assuring everyone that Enlist Ahead will set the bar high with all the resources to educate users of the Enlist system.