Double spray nozzles cut costs, not control

If two heads are better than one, as the old saying goes, should two nozzles together work better on your sprayer? Researchers at Ohio State University (OSU) say yes. And they've developed and patented a sprayer to prove their point.

The double-nozzle technology uses half as much chemical, or less, as a standard sprayer, but provides equal or better results. In tests with Roundup, the scientists found that they could apply 33%, 50%, 75% or 100% of the label rate and get better results in each case than using an 80% rate with a standard sprayer.

The double-nozzle design evolved from research aimed at discovering why small droplets work better than larger ones in laboratory tests, but never work as well under field conditions. The scientists discovered that large droplets aren't very effective as chemical carriers, but they're needed to carry the smaller droplets into the canopy. The smaller drops "draft" behind the larger droplets and then attach to the plant rather than drift off into the environment.

"So the question was how to put only water into the big droplets and only pesticide into the small droplets," says OSU entomologist Robin Taylor.

"The answer was the double-nozzle sprayer that uses one nozzle to shoot a fine spray of pesticide into the spray pattern of a second nozzle that creates coarse droplets of water," he says. "The big droplets pull the small ones into the crop, but they don't carry pesticide and they don't contaminate the environment."

OSU owns the patent for its double-nozzle system and is licensing it to Spray Redux LLC, Cleveland, OH. A retrofit kit for a typical 20-nozzle sprayer is $2,200. For more information, contact Spray Redux at 216-432-4198.