Key Issues Perspective: Herbicide injury to corn unacceptable
Corn growers won’t accept any crop injury as they shoot for higher and higher yields. Anything that might set the corn back or lower yield, even if it might only be one or two bushels per acre, is unacceptable today.
With that in mind, growers expect any corn herbicide they use to be “completely safe” to the crop, whether it is pre-emergence or postemergence herbicides.
“In the corn market today, growers will not stand for any type of injury. Postemerge products for corn production cannot twist, burn or put spots on the leaves; growers just won’t stand for it,” said Tommy Thompson, Sanders area manager for western Kentucky. He knows grower attitudes because he has worked in the ag retail business for more than 30 years and watched the evolution of farmers being happy growing 150-bushel corn to now looking to grow 250-bushel or more corn per acre.
“The worst thing you can do is go in and burn a guy’s corn crop with a postemerge product. Even if you tell him it’s going to be OK, he isn’t going to be happy,” Thompson continued. “Customer satisfaction is what you are looking for, and if a grower isn’t happy with a product, he isn’t going to come back for a repeat performance next year.”
With multiple choices of products that control the same weeds, Thompson said, low use rate, ease of tank mixing and assurance of no crop injury are three major factors that sway growers to use one herbicide over the other. The grower doesn’t care what makes the herbicide safe to the crop, just that it is extremely safe to the crop so that it doesn’t inhibit yield.
Crop safety, because of the safener included, is one reason why Thompson has recommended Capreno for use alone and with tank mix partners. The safener keeps the actives in Capreno harmless to the corn plant as well as safens the tank mix partners.
What also impresses Thompson is that even with the addition of the safener, Capreno is a low-use-rate product.
“If you are spraying Capreno and a growth regulator like dicamba added to the mix, the safener in Capreno will safen the crop to dicamba, too,” explained Daren Bohannan, Bayer CropScience technical development representative for central and northern Illinois plus Wisconsin. Because Bayer CropScience is the manufacturer of the safener, it doesn’t skimp on the safener included in its safened herbicides, he added.
“All herbicides, to be safe for use on a crop, must be metabolized by the plant, and speeding up the metabolism process makes it highly unlikely for any injury to occur, and that is what our safener does,” said Bohanan. “Herbicide safeners are definitely our expertise in both the early pre and post markets.”
He said, “Bayer CropScience currently has three commercialized safeners, and we have others that are not on the market yet as we are testing them trying to find the right marriage of herbicide and crop.”
“The safener increases the plant’s production of some key enzymes that break down herbicides and this speeds up the metabolization of the herbicide. In most cases when we see crop injury from a postemergence herbicide, there were some environmental or adverse conditions that didn’t allow the plant to break it down rapidly enough. Having the safener there ensures that this slow down doesn’t happen.”
A slow down in metabolization doesn’t always have to be leaf damage; it can be things such as stalks susceptible to brittle snap or bottleneck shaped ears, which aren’t immediately seen after a herbicide application, Bohanan noted.
He said, “Even if a herbicide shows 95 percent crop safety, why not shoot for 100 percent safety, which is what we’re doing by adding a safener.”