First-let me say I think the jury is still out here. It is for me anyway. I believe Purdue U. guy says same in Clint Hawk's link. There is obviously damage in some people's fields. Not everyone's though...I am absolutely sure of that!

I believe ground rigs 1st got blamed because of higher gpa carrier rate, not because of mechanical damage. I suspect most hi-clear sprayers shot for 20 gpa if they had the tanks for the job vs airplanes running 2 gpa on low end, 5 gpa on high end. Also, ground sprayers probably had tips about 6-12" above highest leaves...if they could reach that high. That fact, coupled w/tips that typically concentrate towards middle (over plant) is causing question for "concentration" vs an airplane which is probably dropping 2 gpa from 10-20' above crop canopy.

BUT-some on this forum are reporting damage from both air & ground. So much for hi-dose or concentration theory.

Then the "off-label" application timing gets thrown in. As one poster pointed out, about the only thing printed "off-label" would be application within a day or 2 of combining. Again, I believe they apply Headline to sweet corn much ahead of tasseling.

Something is still being missed. Also-this is apparently an area thing, I think.