Thanks to Jeff Cook, County Agent in Peach/Taylor:
With new regulations going into place for the 2018 growing season, now may be a good time to make some adjustments on your pesticide sprayer.
Label requirements for the new Dicamba (Engenia, XtendiMax, or Fexapan) or the 2,4-D (Enlist Duo or Enlist One) technology will force growers to use spray tips that deliver much coarser spray droplet than they are currently spraying.
Contact herbicides like paraquat, glufosinate, and reflex require much finer droplets for maximum coverage. Many of the spray tips that are currently in use produce spray droplets a little bit larger in diameter than a human hair. Droplet size requirements for the new auxin herbicides will be extremely coarse to ultra coarse range. Droplets between the size of a staple and a paper clip.
Systemics like the auxin herbicides move into and throughout the plant so complete coverage is not as important. UGA research has shown similar weed control when using these nozzles. However, since contact herbicides require finer droplets it may force growers to look at either retrofitting booms with multiple nozzle body assemblies or purchasing sprayers dedicated to the new technology.
To assist growers make the change, several companies are providing spray tips to growers for the upcoming season.