Farmers battling tough, resistant weeds are still waiting for help. One of the technologies that should help is the Enlist Weed Control System from Dow AgroSciences. Now in the works for a long time, Dow AgroSciences officials say approvals are coming in from regulatory agencies, but they still don't have all the approvals they need to launch the new 2,4-D tolerant soybeans and herbicides that can be sprayed on them. The goal is still to launch in 2015.

Drift demo: Dave Hillger shows that straight water, sprayed from the nozzle on the left, produces many more fines than when the new formulation of Enlist, minus the active ingredient, is sprayed (right)

Dave Hillger, Enlist field specialist, recently demonstrated why the new formulation is much safer to other crops than original 2,4-D types. While it will still take management and stewardship, Hillger says there is far less risk of off-site injury than before when 2,4-D ester or amine were applied.

Related: EPA Comment Period Closes on Enlist Duo Herbicide

He fires up a sprayer simulator with water in one container and the new Dow formulation, minus the active ingredient, in the other. After a few seconds of operation, particles began to float off and form a small cloud that drifted away on the water side. "Those are fines that are moving of target," he explained.

In contrast, when he operated the spray tank feeding the Dow AgroSciences formulation into the simulated boom and nozzle, the spray did not form the mist or cloud of small particles and did not drift off. He says it's because of the innovative formulation developed by Dow AgroSciences just for this purpose.

He also stressed that nozzle selection would be important. The goal is to select a nozzle that delivers adequate coverage of the target weeds but yet doesn't produce tons of fines that are more prone to drifting off target.

Related: USDA Releases Final Environmental Impact Statement on Enlist Corn, Soybeans

Such factors as keeping boom height within two feet of the crop instead of five to six feet in the air will also be involved, Palmer says. The higher the boom height, the greater the chances that wind can interfere before the spray reaches the weeds in the crop.