Across U.S. farm country, weed management is a top concern of farmers, driving seed and herbicide decisions as they seek effective weed control to preserve yield potential.

This is true of almost every state that grows soybeans, from North to South. Farmers have been using multiple modes of action, pulling out the plows and even hiring chopping crews to try to manage resistant weeds in their fields.

Five years ago, Dennis Wentworth, who farms soybeans in central Illinois, began having waterhemp break through, despite his standard weed control program of pre-emergence residual herbicide followed by Roundup PowerMAX® herbicide in Roundup Ready® soybeans. Watching the problem get worse in subsequent seasons, he and his farming partners made adjustments to the herbicide program in an attempt to get a handle on things.

"Finally, in 2017, weed control was below our expectations and our threshold of tolerance," says Wentworth. "The issue with waterhemp, versus all the other weeds we have, is that waterhemp produces many more seeds on one plant than other weeds, and the sheer number of seeds left in a field over the winter creates a problem next season."

This volume of weed seed is what makes waterhemp so daunting, according to Wentworth. "We were once satisfied with 95 percent control," he recalls. "Ninety-five percent control is just not acceptable in resistant waterhemp because you're building the seed bank up rapidly, even with just a few plants left in the field."

In hopes of getting cleaner fields, Wentworth and his farming partners walked every acre to pull waterhemp from the fields where their herbicide program did not provide control. Prior to the introduction of the Roundup Ready Technology in the late 1990s, walking fields and pulling weeds was standard practice. Today, with thousands of acres of soybeans, plus corn to manage, the time spent pulling weeds from fields has become cost-prohibitive.

"Whether you practice tillage or walk fields to pull weeds, you'll see those things cause time management issues, as well as mechanical issues, that we don't need to spend time dealing with," says Wentworth. "Our large farming operation is built on a management system, taking into account machinery needs, seed, herbicides, fertility. They are all part of a management system, and once things get outside of the system, they get expensive really quick."

In order to get back to timely, effective weed management, farmers are adopting new herbicide technologies such as Roundup Ready Xtend Technology.

Effective Control Builds Demand

Acreage planted to Roundup Ready 2 Xtend® soybeans doubled from upwards of 20 million in 2017 to more than 40 million in 2018, indicating the strong need farmers have for this technology.

"We've planted all Roundup Ready 2 Xtend soybeans the last two seasons, and we have had the cleanest crops we've had," says Seth Taylor, who farms in Obion County, Tennessee, a hotbed for resistant Palmer amaranth (pigweed) and marestail. "It's a lot more cost-effective to use. Without the system, our weed control costs would increase significantly because of the other herbicides we'd have to use."

The technology has helped Ben Buesing get resistant waterhemp and giant ragweed under control on his farm in Richards, Missouri. Flexibility and weed control are the big advantages he has experienced with the technology. The ability to make dicamba applications right up to planting offers both a planting time burndown as well as up to 14 days of soil activity on certain small-seeded broadleaf weeds, he says.¹

An early postemergence application that includes XtendiMax® herbicide with VaporGrip® Technology, a restricted use pesticide, helps set the table for a clean field early in the life of the plants.

"Having an effective herbicide option that provides great control of the tough-to-kill weeds we have has helped us considerably. One of the biggest benefits of the herbicide we have experienced is the broad application window from pre-emergent up to the day we plant and on through our early post application that gives us flexibility when the weather doesn't cooperate," says Buesing.

"It's a great tool. I've gotten excellent weed control, and the genetics of the soybeans are outstanding. The system provides good weed control, and good yield is there at the end of the year."

Roundup Ready Xtend Technology includes XtendiMax with VaporGrip Technology, one of the primary labeled dicamba formulations for use in Roundup Ready 2 Xtend soybeans and Bollgard® 3 XtendFlex® cotton. Using XtendiMax with VaporGrip Technology, along with pre-emergence and postemergence residual herbicides and Roundup® brand agricultural herbicides in the postemergence application, has been proven on millions of acres to help farmers improve weed management and set the crop up for maximum yield potential.

Together, dicamba and glyphosate can control more than 270 species of weeds, especially tough-to-control broadleaf weeds such as Palmer amaranth, waterhemp, marestail, lambsquarters and velvetleaf. XtendiMax with VaporGrip Technology offers up to 14 days of soil activity on certain small-seeded broadleaf weeds.

"Roundup Ready Xtend Technology allows farmers to be timely with herbicide applications," says Ty Witten, North American Crop Protection Lead, Bayer Crop Science. "It offers farmers flexibility with the opportunity for in-season, over-the-top dicamba applications and precise, on-target applications. Farmers also tell us they've seen a decrease in the number of trips made across fields, especially tillage trips."

Steve Boland planted Roundup Ready 2 Xtend soybeans on his Iowa farm for the second season in 2018 and made applications of XtendiMax with VaporGrip Technology.

"I've been very satisfied with the weed control that I received from XtendiMax with VaporGrip Technology," he says. "I saw clean fields. I would definitely recom-mend the program to other farmers who struggle with weed problems. I think it's a great system."

Weed control and yield are key factors farmers consider when making planting decisions. In nationwide herbicide systems trials in 2017, Roundup Ready 2 Xtend soybeans held an average 5.7 Bu/A advantage over LibertyLink® soybeans.² Farmers are advised to base planting decisions on profitability, and that begins with yield potential. The Roundup Ready 2 Xtend soybean lineup offers diverse genetics, tested and proven over many seasons.

The way to keep the technology available is to remain on-label, says Iowa farmer Rodney Greiner.

"Keeping this technology well into the future means staying on-label with weed height [and] herbicide rates and using required surfactants that go with it," he says.

Back in McLean County, Illinois, all the soybean acres at Wentworth Family Farms were planted to Roundup Ready 2 Xtend soybeans in 2018.

"As far as weed control, it has done what it is advertised to do, and we want to keep that going as long as possible," Wentworth explains. "You have to respect the technology, and you also have to respect the restrictions on the label that this technology has, so we are trying to be good stewards of the technology."

By: Al Fava