Pigweed, waterhemp, Palmer amaranth. Anyone who grows corn or soybeans despises those weeds and how quickly they can ravage a field.
Dave Johnson is a product development manager for DuPont Crop Protection. He says there is no “silver bullet” to get rid of weeds, so implementing several weed control tactics can give you the upper hand.
"Starting clean. If you’re no-till, use an effective burn-down herbicide program, and then at planting, use an effective multiple mode of action pre-emergence herbicide. Again, we want to hit these weeds in a number of different ways. And then, scouting your fields to make sure that you understand when the weeds are starting to emerge so you can spray them when they’re early," says Johnson. "Weeds are much easier to control when they’re small. Once they get over about 4” tall, it’s just becoming more and more difficult to control them."
Killing a weed is always easier before it comes up. Those tiny Palmer amaranth seedlings that just poked through the soil can grow two-to-three-inches-per-day. When control measures are put off until weeds are larger, the yield loss can be up to 20-bushels-per-acre.
Don’t cut back on your control efforts to save money. Johnson says Palmer amaranth and its weedy friends will continue being a fight for farmers this year.
"I think we’re still going to be dealing with the waterhemps and the Palmer amaranth, and our no-tillers are going to have to deal with marestail. Out west, we’re going to see Kochia," he says. "Again, there’s no silver bullet to any of these, and I encourage growers to work with their local retailers, their local advisers to develop the best programs for their situation."
Scout your fields, and take good notes on where the weeds are to help you plan your strategy.
Learn more about why it's best to whip weeds when they're small