We recently talked with several growers about their success in the fields and how they maximize their corn yields. For example, what combination of products do they use and why? This is what these growers and their representatives had to say. “Corn growers who use Corvus have an important tool in managing weed resistance and herbicide-resistant weeds while they get better weed control,” says Jeremy Quist, Crop Science technical consultant in Nebraska. “They can adjust the rate to compensate for low organic matter or high pH. At a low use rate, they get burndown and reactivation in no-till and conventional till.
Managing Resistance
“With Corvus herbicide, corn growers can control glyphosate-resistant weeds like waterhemp and velvetleaf more effectively than with the competition,” explains Gary Griffith, a Nebraska-based Crop Science sales representative. “This product will take out these resistant weeds with the pre-emergence application.”
Chris Hansmeyer, in Hallam, Neb., found a two-pass system works best in the no-till operation he runs with his father. “Instead of using straight Roundup® herbicide, we always break it up with a pre [like Corvus] in the spring,” he says. By using two modes of action, Hansmeyer controls resistant weeds and prevents further resistance from developing.
“A pre application is really what makes the Roundup Ready® program work well. We don’t have any resistant weeds because we change our mode of action every time we spray. We use Laudis® herbicide and Roundup herbicide postemergence,” he says. “Our fields usually stay clean all season.”
Boost Your Profit Potential
Adding Stratego® YLD fungicide to the second pass has been profitable for Keller and his customers. “We’ve seen huge results with Corvus down in front of Roundup Ready corn. We come back with glyphosate, Laudis and Stratego YLD postemergence at from V4-V7, and it’s very beneficial.”
“There is a real profit opportunity with the second pass when you add Stratego YLD,” Quist points out. “You have better weed control and improved yields. With the V4-V7 timing, growers can also add foliar nutrients. Stronger, healthier plants are less prone to lodging. When corn is lodged, you are forced to reduce speed to minimize yield losses. Slower speeds increase harvest expense.”
Both Keller and Hansmeyer have seen reactivation help provide that consistent, reliable weed control. When it rains, “you’ll see the little button weeds and a bit of grass come up and turn brown,” Keller says. Hansmeyer has also seen reactivation control velvetleaf and grasses.
“Used as part of a two-pass system, Corvus worked well for us,” says Steve Althouse from Waverly, Neb. “We plan to use it again.”
Strategies for Success
Get a clean start for your crop with burndown and an early-control pre-emergence pass. “Use a minimum of 10 gallons of spray mixture per acre,” says Jeremy Quist, Crop Science technical consultant in Nebraska. “Uniform, thorough spray coverage is important to achieve consistent weed control. Coverage is a factor of spray volume and pressure.”
After years of using glyphosate, the standard post application has been five gallons of water applied in large droplets to minimize drift. “To maximize the foliar activity of Laudis, growers need to use 10 to 20 gallons of water per acre delivered in medium spray droplets, at a minimum,” Quist says. “Use the best adjuvant and the highest recommended rate for increased efficacy.”
Herbicide Mixing
An added benefit of applying Laudis as the second pass of a two-pass program is the opportunity to tankmix the postemergence herbicide spray with an early season application of Stratego YLD fungicide. Laudis can be tankmixed with Stratego YLD fungicide and applied from the V4 to V7 growth stages, optimizing weed and disease control with fewer passes.
To better understand the details of herbicide mixing, reference the chart below for product recommendations for a two-pass system in no-till and conventional-tillage corn.
Product |
Herbicide Application Rate |
Tankmix Partner |
Timing |
Corvus herbicide |
3.3 fl. oz./A,
coarse soils, less
than 2% organic
matter or pH of
7.5 or greater 4.0
to 5.6 fl. oz./A,
all other soils |
Atrazine, optional
if permitted |
Pre-emergence,
10 gallons of
water per acre |
Laudis herbicide |
3 fl. oz./A |
Glyphosate +/-
atrazine |
Postemergence up to
the V9 growth stage,
10 to 20 gallons of
water per acres in
medium droplets |
Corvus Outperforms
“Corvus herbicide provides control of a broader weed spectrum than Bicep II MagnumTM, Harness® XTRA or Keystone® at a much lower herbicide application rate,” Quist explains. “In no-till, Corvus herbicide is more effective than Lexar® herbicide, again at a much lower rate. SureStart® provides OK control, while Corvus provides excellent control.”
Bayer CropScience LP, 2 T.W. Alexander Drive, Research Triangle Park, NC 27709. Always read and follow label instructions. Bayer (reg’d), the Bayer Cross (reg’d), Capreno®, Laudis® and Stratego® are trademarks of Bayer. Roundup, Roundup Ready and Harness are registered trademarks of Monsanto Technology LLC. Lexar, Magnum are trademarks of a Syngenta Group Company. Keystone and SureStart are trademarks of Dow Agrosciences. Corvus is a Restricted Use Pesticide. Corvus, Laudis and Stratego YLD are not registered in all states. For additional product information call toll-free 1-866-99-BAYER (1-866-992-2937) or visit our website at www.BayerCropScience.us CR0313CORVUSA061V00R0