Using Roundup (glyphosate) alone, some soybean producers have trouble controlling morningglory, velvetleaf, coffeebean and other problem broadleaf weeds. Tank mixes are often the solution. According to Valent, one tank mix being adopted is Resource/Roundup.
Resource isn't a new product, said Cam Smith, Valent southern row-crop market segment manager. “We've had Resource labeled for quite a few years for high use rates. Primarily, it was being used in non-Roundup Ready soybeans in the Midwest against velvetleaf and some other broadleafs.”
A few years ago, while working in Tennessee, Smith and colleagues mixed Resource with Roundup. “We wanted to see how (the mix) handled morningglory and other weeds Roundup alone was weak on. Lots of other products — Reflex, Classic and others — were already going into tank mixes for morningglory control.
“We knew Resource had similar activity on morningglory and pigweeds. But, until then, Resource had been sprayed on these weeds at high rates alone. So we put 2 to 4 ounces of Resource in a mix with Roundup.”
Researchers — both university and Valent-employed — found the tank mix controlled morningglory, teaweeds, pigweed and some other weeds that Roundup, even at high rates, wasn't effective on.
“Since then, we've had a consistent market for increasing activity of Roundup,” said Smith. “We've also brought speed to the field. As a sales rep, it was easy to sell speed. Farmers can look at Roundup applications and see activity in a week. If a farmer adds Resource, he'll see activity quicker — often in two or three days.”
As a tank mix with Roundup, Resource has a label for 2 to 4 ounces. It has an aerial application label as well.
To save money, some producers try to trim Roundup rates. “We don't recommend that — we prefer producers use the rate suggested,” said Smith.
As a tank mix with Roundup, Resource is being used in many soybean-growing areas.
“The Midwest is picking up on it where Roundup Ready soybean acres are pushing 98 percent. But, other than the sales reps pushing Resource, there hasn't been a huge focus on it. I feel if the producers know about it, its use will grow. Folks that try it, embrace it. Very few have anything negative to say.”
Smith said producers in the Missouri Bootheel, Arkansas and Tennessee were some of the early adopters of a Resource/Roundup mix.
“Those areas were some of the last to adopt Roundup Ready soybeans. But because they waited so long and were so used to farming clean, they were some of the first to use Resource.”
Chad Powell, a soybean producer near Coy, Ark., has used Resource/Roundup for several years. “I've found the Resource adds to my glyphosate tremendously, especially on morningglory control. Morningglories are the main reason we use it. They've always been a problem around here.”
Some other growers in the area have picked up on the tank mix, said Powell. “Around here, most soybean farmers tank-mix something with glyphosate. Many use Classic and that's fine. I don't get as much crop injury with Resource as I do with some of the other add-ins, though. And I know I get better control of morning-glories. It's quick. Within a week, the morningglories are curled up and dead.”
The biggest challenge in using a tank mix “is the cost of generic glyphosate has gotten so cheap,” said Smith. “Sometimes the question isn't whether producers will add anything to a tank mix, but whether they'll just spray more Roundup.”
That approach, unfortunately, can lead to resistant weeds much quicker. Consistent application and consistent misses breed resistance.
“It used to be, resistance management was just something companies worried about and hoped farmers paid attention to… I don't want to use that as a fear factor to sell Resource, but as a weed scientist, I can tell you that's the way it is,” said Smith.
“One of the angles we've taken with Resource is preventing resistant weeds. Sure, you can add another quart or pint of Roundup, but is that good science? What will that mean a decade from now when morningglories are more trouble than ever? On problem broadleaf weeds, (a Resource/Roundup mix) provides consistent, fast action and a complete kill.”