When Dow AgroSciences brings Enlist Duo to market, likely in 2015 or after, the label will recommend drift-retardant nozzles for applications. It's part of the system that will make the application of Enlist Duo on 2,4-D resistant crops safer as far as crop injury to non-target crops.

The problem with 2,4-D is the tendency to drift and volatilize, allowing it to move off target. However, Damon Palmer with Dow AgroSciences insists the product applied over the 2,4-D soybeans will be an approved product. The application of 2,4-D amine or ester will not be labeled. Anyone doing it will be off-label.

Right combination: This spray table demonstrates differences in product technology and nozzle technology that will be used to minimize drift with Enlist Duo once it is approved for use.

"We were able to develop a molecule using what we call Colex-D technology that minimizes variability and cuts drift potential by close to half," he says. You can gain the other half of drift reduction by using air induction nozzles. When used as a system, Palmer insists neither volatility nor drift will be an issue.

Dow AgroSciences won't supply air induction nozzles to growers, although there may be some incentives to help offset the cost later. The air induction or other drift-retardant nozzles will be strongly recommended.

"We're finding that many farmers are already using these nozzles," he says. "We don't think it's going to be a big hardship for farmers to come up with air induction nozzles to apply the product."

Palmer uses a spray table to illustrate how the difference in nozzles and droplet size affects drift. If droplet size gets too large, however, then coverage of the plant with the product becomes an issue. He believes that nozzles they will recommend will hold down drift but yet deliver the type of weed coverage necessary for good control.

Changes in the molecule made in the lab took the drift reduction about half-way, he summarizes. With the right nozzle, you pick up the other half and make drift nearly a non-issue. That sill assumes good stewardship, such as not spraying when it's too windy.