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509 - Roundup Ready Era Begins

Weed control has long been the number one production problem facing sugarbeet growers in MN, ND and throughout the USA. This new technology will make weed control much, much easier. American Crystal growers are reminded to abide by all the rules of the 2008 Monsanto Technology/Stewardship Agreement and to read and follow the applicable sections of the TUG (Technology Use Agreement) which is part of their overall stewardship agreement. The Roundup® use recommendations for weed control from Dr. Alan Dexter are summarized in the next three sections.

First Roundup Application Timing to Avoid Competition Loss

  • Light weed pressure- 2-leaf to 4-leaf beets
  • Moderate weed pressure- 2-leaf beets
  • Heavy weed pressure-cotyledon to 2-leaf beets
  • Apply 22 to 28 ounces of Roundup

Factors That Influence Timing the Second Roundup Application

  • The label requires it must be 10 days after the first application
  • Determine if more weeds emerged
  • Determine size of new weeds-spray large weeds sooner
  • Determine number of new weeds-spray dense weeds sooner
  • Dr. Dexter suggests 14 to 21 days after first application for most situations

Tips on Maximizing Weed Control with Roundup

  • Weed control is best between 10 a.m. and 4 p.m.
  • Add 8.5 to 17 lbs of AMS per 100 gallons of spray solution.
  • Weed control is often better with spray volumes at the low end of the range.
  • Rain within 6 hours after application may reduce weed control.
  • Avoid spraying with dust on plants.
  • Avoid spraying with dew on plants.
  • Cool weather slows activity and time needed to kill weeds.
  • Frost before application will reduce control.
  • Drought slows weed growth, reduces Roundup activity.
  • Delay cultivation at least 3 days after Roundup use to maximize control.
  • Air temperature over 85 F during application can reduce weed control.
  • Don't spray after sunset-weed control can be reduced.

Questions and Answers: Roundup Ready Sugarbeets

Can a Grower Use a Generic Glyphosate Product?

  • ONLY if it has federal, North Dakota and Minnesota state approved labels specifically for post emergence use.
  • Yes, but he would no longer qualify for the Monsanto's reward program for other Roundup Ready crops.
  • The Rewards Program states Roundup brand herbicides must be used on all Roundup Ready crops in a farming operation.

What is the Monsanto Reward Program for Sugarbeets? 

  • If a Roundup Ready sugarbeet crop is determined unacceptable for maintaining through harvest by the earlier of either (a) 60 days after planting or (b) July 15 of the current production year, the grower will not be charged the Herbicide Tolerance Payment (HTP or Tech Fee) for the units of seed used to plant such crop, provided the grower does not replant with Roundup Ready sugarbeet seed.
  • There may be additional enhancements to the programs to support the use of Roundup on sugarbeets but they have not yet been finalized.

What happens if Roundup Ready Sugarbeets Have to Be Replanted?

  • If a grower replants with another seed company Roundup Ready variety - the seed company with the original seed refunds that tech fee, the alternative seed company supplying the Roundup Ready replant seed will then collect the tech fee.
  • Growers only pay the tech fee once per year.

Can Growers Tank Mix Other Pesticides or Agrichemicals With Roundup?

  • Yes, if all components of the tank mix are labeled.
  • Monsanto does not recommend tank mixes. Tank mixes void the Monsanto warranty regarding weed control and crop injury.

Must Growers Top or Rogue Bolting Sugarbeets From a Roundup Ready Sugarbeet Field?

  • Agreements with Monsanto state "bolting plants must be removed or topped before they produce pollen or seeds."
  • American Crystal also recommends this as good stewardship of the technology.

Contact your agriculturist for assistance in using this new technology to its best advantage.

Avoid spray drift - never apply roundup in a wind inversion condition. Use drift control techniques to minimize any chance of an off target application from occurring.

Roundup PHI is 30 days prior to harvest. Read and follow all label requirements.