Look at the middle rows of soybeans in the picture. Why are they shorter and have less total growth than the soybeans on either side? Here is a clue. The spray tank was contaminated with 5% of an herbicide that causes injury and plant death when sprayed on soybeans that don't have the tolerance trait for that chemical.
The picture is from a demonstration plot at Beck's emphasizing the need to be careful both with recording what is planted where, and in cleaning out the herbicide tanks and entire sprayer system thoroughly before switching products.
The demonstration was repeated to represent 0.5% contamination in the tank with herbicide from a previous application. The results weren't as dramatic, but were still evident.
Products used in the demonstration were some of the new herbicides to be applied on crops with specific traits that allow tolerance to those herbicides. The new group included Enlist Duo from Dow AgroSciences, Xtend from Monsanto and Engenia from BASF and Balance Bean from Bayer.
Fred Whitford, director of Purdue University Pesticide Programs, spent two years learning the ins and outs of sprayer tank clean-up. He wasn't exactly undercover – the people he worked with knew what he was doing. But he took his camera along as he followed experts in the industry who know how to clean sprayer tanks properly.
He used the photos and information to prepare a new Extension publication which is anything but your average Extension publication. It's entitled "Removing Herbicide residue from agricultural application equipment," and contains page after page of color photos depicting both good and bad situations in sprayer clean-out.
The bad situations could result in tank contamination. That's never a good thing, but will be extremely costly and even devastating if not corrected once this new era of herbicides becomes more widely used.
Get a print copy for $5.50, or download it free. Visit: edustore.purdue.edu.
Are you confident in preparing your sprayer for the season ahead? Do you know how to best minimize herbicide spray drift? Brush up with our free report, Best Practices For Spraying: Get The Most Out Of Your Sprayer