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Extension > Minnesota Crop News > Recommendations for Managing Glyphosate-Resistant Waterhemp in Roundup Ready® Sugarbeet

Recommendations for Managing Glyphosate-Resistant Waterhemp in Roundup Ready® Sugarbeet

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Written by: Dr. Jeff Stachler, University of Minnesota and North Dakota State University and edited by Al Cattanach, Mark Bredehoeft, and Mike Metzger

Questions from sugarbeet growers have been coming in to Extension and Sugarbeet Cooperative Ag Staff about how to properly manage glyphosate-resistant waterhemp. The three Sugarbeet Cooperatives and Jeff Stachler recently met to determine the best strategy to manage glyphosate-resistant waterhemp in Roundup Ready sugarbeet.

If fewer than 20 waterhemp plants or a single small patch of waterhemp have survived glyphosate in a field for the past two years, we suggest the following recommendation:

Apply Betamix (12 fl oz/A) plus Nortron (4.0 fl oz/A) plus glyphosate (0.984 pound acid equivalent per acre) {lb ae/A} [Roundup PowerMax (28 fl oz/A)] plus Destiny HC, Savvy, Loveland's MSO with Leci-tech technology, or any other high quality, tested, and proven high surfactant oil concentrate (HSOC) that is MSO based and reduces antagonism with glyphosate at a rate of 1.5 to 2.0 pt/A to cotyledon sugarbeet.

At the two-leaf stage of sugarbeet, apply Betamix (12 fl oz/A) plus Nortron (4.0 fl oz/A) plus Outlook (14 fl oz/A) or Dual Magnum (1.5 pt/A) plus glyphosate (0.984 lb ae/A) [Roundup PowerMax (28 fl oz/A)] plus Destiny HC, Savvy, Loveland's MSO with Leci-tech technology, or similar MSO product (1.5 to 2.0 pt/A).

As soon as the sugarbeet stage is greater than 8 leaves, apply Betamix (16 fl oz/A) plus Nortron (4.0 fl oz/A) plus Outlook (10 fl oz/A) or Dual Magnum (1.0 pt/A) plus glyphosate at 0.75 lbs ae/A [Roundup PowerMax (22 fl oz/A)] plus Destiny HC, Savvy, Loveland's MSO with Leci-tech technology, or similar MSO product (1.5 to 2.0 pt/A). At 10 to 14 days after this last application, scout the field to determine the need for a fourth application of glyphosate (0.75 lb ae/A) plus Betamix (24 fl oz/A) plus Destiny HC, Savvy, Loveland's MSO with Leci-tech technology, or similar MSO product (1.5 to 2.0 pt/A).

Other options to consider at 10 to 14 days after the third postemergence application include row-cultivation, hand-labor, or row-cultivation plus hand-labor.


If the glyphosate-resistant waterhemp density exceeds 20 plants per field, then Nortron (7.5 pt/A) should be incorporated prior to planting and apply the same postemergence treatments as above beginning when waterhemp plants are in the cotyledon stage of development. If this first postemergence application is applied at or shortly after the two-leaf stage of sugarbeet start by applying the 2 leaf treatment listed above. Apply all subsequent applications every 14 days as necessary, always applying the highest legal rate of Betamix based upon the stage of the sugarbeet and do not apply greater than 12 fl oz/A of Nortron postemergence for the season. Ro-Neet SB (5.3 pt/A) can be incorporated or Dual Magnum (1 to 2 pt/A) can be applied preemergence instead of Nortron due to lower herbicide cost and similar control of waterhemp. If Nortron, Ro-Neet, or Dual Magnum is applied to the soil in a band, row-cultivation and hand labor will be required to maximize waterhemp control.

We have suggested specific rates for Dual Magnum, Nortron, and Ro-Neet for fine textured and high organic matter soils. If the soil-type in the field is coarser and has low organic matter content, then the rate of these products need to be adjusted accordingly.

Waterhemp management in all crops must be taken seriously to maintain the effectiveness of glyphosate and Roundup Ready sugarbeet or waterhemp will become a very serious production problem due to the enormous quantities of seed produced by a single plant and how easily seed can be transported to other fields.

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