From selecting a soybean seed and herbicide system, to planning the products that make up your weed management plan, having choices is essential for weed management success.
As the competition against weeds intensifies, growers have more choices than ever before and it’s critical they choose the system best tailored for their field conditions. Identifying problematic weeds and selecting the right treated seed is the first step to starting 2019 on the right foot.
Looking back at 2018, Iowa soybean growers started off the year with a never-ending winter followed by significant weed pressure.
“Winter annuals and marestail are the biggest problem weeds for no-till acres in Iowa,” shared Mark Storr, BASF Senior Technical Service Representative from Nevada, Iowa. “However, waterhemp and now Palmer amaranth are the key drivers all across the state.”
With these problematic weeds in mind, selecting the right seed and herbicide system with rotating modes of action to help reduce growers’ “weed-seed bank” is critical. Growers are quickly losing efficacy on both Palmer amaranth and waterhemp due to growing resistance. However, group 15 products are most effective on these two weeds for preemergence and for post-emergence, Liberty® and Engenia® herbicides are still effective options.
“At the start of the season, growers want to know the most efficient and effective ways to reduce the amount of weed seeds they have in their field to protect their yield,” said Bill Backhaus, BASF Iowa Seed Agronomist. “There are a lot of choices out there and starting off with a strong PRE followed up with a choice of your herbicide program will help extend the residual control of weeds such as waterhemp, which is continuing to display strong levels of adaptation and resistance development in Iowa fields.”
North Central Iowa grower Jim Legvold, who farms 1,300 acres in Humboldt, Iowa, has been a conventional tiller, no-tiller and now strip tiller. Two of his concerns in 2018 when it came to his beans were waterhemp and marestail.
“Once weeds germinate you’re behind the eight ball, specifically with beans. You need to start clean to stay clean or you’ll be fighting weeds all year round,” said Legvold. “A residual herbicide needs to be down to have success in keeping the weeds away. With these tough economic times, it’s important to get the biggest bang for your buck.”
Having seed and weed management system choices with rotating modes of actions, allows growers to become better stewards of the land to help ensure their operation is around for future generations. Two popular options growers can choose from are dicamba-tolerant and LibertyLink® cropping systems.
“We want to control our weed-seed bank and keep it down for the future generations of farming,” said Backhaus. “When it comes to deciding on an herbicide program, it comes down to the grower’s choice and what technology they are most comfortable using on their farm. There are limitations and advantages for both Engenia and Liberty herbicides. Working with your local retailer can help you decide what system is best for your operation.”
To select the best bean system that fits your operation, look at the weeds you have to inform what system will allow you to control the weeds best. One new seed option for 2019 is Credenz® LibertyLink GT27™. These varieties allow growers greater flexibility when it comes to managing weeds. With tolerance to both Liberty herbicide and glyphosate, growers can now include glyphosate with Liberty herbicide applications.
“Selecting varieties to succeed this year depends on your management style, herbicide system choices, desired variety characteristics and germination rates,” Backhaus said. “Double check germination on seed, be prepared to adjust if needed, and do whatever you can to protect it with a full seed treatment, strong herbicide system, and post fungicide and insecticide applications as needed to protect yields throughout harvest.”
“Since I’m not tilling my land, I have to even more carefully manage the weeds on my operation,” Legvold said. “As a strip-tiller I put down a preemergence herbicide that includes a residual to carry through and help me manage the grasses.”
Legvold feels strongly about using a residual herbicide preemergence along with a “kicker” herbicide to control any emerged weeds. In 2018, his PRE-herbicide plan on his dicamba-tolerant soybeans included Zidua® herbicide, glyphosate and Engenia herbicide to help clean up his field after weeds started to germinate as a result of later planting at the end of May. Engenia herbicide is a US EPA restricted use pesticide and additional state restrictions may apply.
“I needed a good kill with the weeds being higher than I wanted due to later planting this year,” Legvold said. “Roundup doesn’t do it all anymore, and I needed to layer in different products preemergence to get all of them.”
Legvold and Storr believe residuals will be critical to weed management success in the coming year.
“BASF has great options and solutions with Zidua herbicide or Zidua PRO as a PRE to prevent those weeds from germinating, and you can clean them up with products like Liberty or Engenia should they require it,” said Storr.
“On a strip till or no-till operation, you need a good group 15 herbicide that has great staying power on small-seeded broadleaf weeds, so Zidua will be the backbone of my plan for 2019,” said Legvold.
Of course, it is critical for growers to always read and follow label instructions that correspond with the products in their integrated weed management plan.
As a soybean grower, you have a lot of choices to make. Are you going to implement tillage? What seed are you going to plant? How will you manage your weeds? But starting this year with a clean field either through tillage or an effective burndown herbicide, followed by an effective group 15 preemergence and a timely post-emergence application will help you best manage weeds. Consulting local, trusted advisors like BASF reps Mark Storr and Bill Backhaus is also critical for Iowa soybean growers to overcome and learn from last year’s challenges as they meet 2019 head on.
Engenia Herbicide is a US EPA Restricted Use Pesticide. Additional state restrictions may apply.
Always read and follow label directions.