Key Issues Perspective: Seed companies teaching weed control
Liberty herbicide weed control system resulted in a clean LibertyLink soybean field. Farmers are notorious for not believing that they can learn from farmers in another state, but the spread of herbicide-resistant weeds is changing that mind set.
Turk Regennitter, general sales manager for Merschman Seeds with headquarters in West Point, Iowa, said the seed company has had a “large presence in the bootheel of Missouri where serious weed resistance has occurred. We watched the pigweed resistance grow from its infancy in that area to being a major problem in many states.”
“We felt it was our obligation to our customers (in seven states) to forewarn them about what was coming and the changes that would be needed to be made to preserve any technology,” Regennitter said.
When the seed company representatives started talking to farmers outside the bootheel, the reaction was “those guys down south don’t really know how to farm like we do up here.” But the reality is that farmers north and south have to grow soybeans using similar methods and products to counter glyphosate-resistant weeds in soybeans, the Merschman representatives have countered.
The similar control system is for a pre-emergence herbicide followed by a postemergence herbicide when escaped weeds are small, no larger than four inches. In the last couple years, it has become easier for Merschman Seeds to recommend the easiest and preferred answer because they have had an increasing number of LiberyLink soybeans, which allows the use of Liberty herbicide. LibertyLink soybeans are being sold by more than 100 seed brands nationwide, today.
The herbicide sprayed over LibertyLink soybeans will not damage the beans and is proven to kill the wide spectrum of glyphosate-resistant weeds. Regennitter noted that the company sells soybean seed in the maturity ranges of 1.8 to 5.4 with LibertyLink seed available in most of this maturity range.
Timing of a Roundup application was a minor concern until weed resistance started showing up, but any postemergence application, including glyphosate, is now only recommended to kill small weeds. Turk said, “Two-inch tall weeds is what we want our customers spraying.”
Alan Hopkins, Bayer CropScience Midsouth area seed technology manager, said, "We strongly encourage growers to target young actively-growing weeds. This will provide the most consistent weed control performance. Achieving maximum weed control and using herbicides with multiple effective modes of action, including residual herbicides, will reduce the risk of weeds becoming resistant to Liberty herbicide."