As Spandl suggests, adding new/old chemistries to the mix is shifting adjuvant priorities again. Jim Reiss, vice president, Agricultural Chemistries, Precision Laboratories, notes that both the new dicamba and 2,4D technologies have very specific requirements to enhance spray quality, and a lot of existing adjuvants can’t be used.

"We are working on replacements for ammonium sulfate," says Reiss. "Drift control is going to be important too. That's where we are spending 70% of our research effort."

If the complexities seem overwhelming, the experts agree on a simple solution. "Go to your local agronomist," says Spandl. "They have experience with the different products applied to the weeds in your area. Ask what is best for your situation and needs."

"While it is difficult even for local retailers to always pick the right adjuvant, they will carry a lineup of products, whether ours or someone else's, that fit your geographic needs," says Kuehl. "Be careful about purchasing products from an unfamiliar source."

That is especially true of imported glyphosate and other off-patent chemistries. While the amount of active ingredient has to be identified on the label, what is unknown is what adjuvants or surfactants might be included.