Three years ago when it became apparent Dow AgroSciences was serious about bringing out technology that would allow spraying 2,4-D on 2,4-D tolerant corps carrying a special trait to confer that tolerance, many farmers and custom applicators were worried. Especially concerned were specialty growers, like tomato growers in north central Indiana, and the company they grow for, primarily Red Gold. Drift and volatilization of products that tomatoes are sensitive too can wreck the production and quality potential of a highly-valuable crop.
The concern grew from the fact that 2,4-D is known to be an old, effective herbicide, but it is also known to drift if sprayed incorrectly, especially in high wind speeds, and to volatilize off the surface, which basically means pick up and move even though the spray droplets hit their original target. Many crops are sensitive to 2,4-D. It's not used on corn as much as in the past, especially on corn of any size, even with drops, because some hybrids react by becoming brittle after 2,4-D applications. Brittle stalks, even for a short period, leaves the crop vulnerable to wind damage.
Dow AgroSciences listened to all the concerns, and from the beginning, knew they were going to introduce a different version of 2,4-D using advanced technology to resolve or greatly reduce drift or volatilization concerns. Just recently, they allowed ag media inside a lab where they demonstrated how their new technology results in significantly less drift and volatilization.
It's called Colex technology, and it involves changes in formulation. Since it's proprietary technology at this point, the 'whys' an dhows' weren't answered. But a demonstration inside a spray chamber vs. an amine 2,4-D formulation, already less volatile than the ester formulation used most commonly, proved that the new formulation developed by Dow AgroSciences is significantly less susceptible to drift. Other demonstrations showed that it is also less volatile.
Even the 2,4-D formulation is different. Instead of being an ester or amine, it's a 2,4-D chlorine, developed for this purpose. The result verified by ag media in the field is that the system appears to be safe, as long as it is sprayed over corn or soybeans carrying the tolerance trait.
No brand name has yet been released for the herbicide that will be part of the Enlist weed control system. Regulatory approval is still under review. The target for release of the system for corn is 2013.