ISSUE #579

579 - Maximizing Glyphosate Effectiveness

5-9-2013

IT IS CRITICAL WE PROPERLY USE ALL HERBICIDE FORMULATIONS containing glyphosate. Proper use maximizes weed control and reduces opportunity for resistant weed development.

USE CORRECT RATES. There are about 70 glyphosate formulations labeled for sugarbeet use. There are 7 different amounts of acid equivalent (active ingredient) being marketed. The correct amount of product to use will vary by nearly 50% depending on your product of choice, see Table 1.

Listing the above formulations

Equivalent Rates for Different Formulations 

Formulation lbs./GalOunces Needed for Different Rates
Acid Equivalent.75 lbs./A.98 lbs./A1.125 lbs.
3.0 32 41 48
3.7 26 33 38
4.0 24 31 36
4.17 23 30 34.5
4.5* 22 28 32
4.7 20 26 30
5.0 18 24.5 28
  • Always apply 28-32 oz./A of the 4.5 Lbs. acid equivalent product or an equal amount of other formulations to maximize activity*.
  • Use lower water volumes to maximize activity.
  • Use larger droplet sizes to maximize absorption and activity and reduce drift.
  • Apply glyphosate to small weeds that are cotyledon to 2" tall to maximize activity and minimize resistance development.
  • Always add correct amounts of AMS to maximize activity.
  • Add the correct NIS to glyphosate products that don't contain the proper amount to maximizeactivity, refer to glyphosate formulations brochure.
  • Apply during the day from 10:00 a.m. to 6:00 p.m. to maximize activity.
  • Glyphosate applications made when humidity is high helps maximize activity.
  • Apply when temperatures are above 65 degrees to maximize activity.
  • Don't apply glyphosate under dusty field conditions that reduce activity.
  • Mixing glyphosate with oil adjuvants will reduce activity.
  • Tank mixes with Stinger will maximize activity on glyphosate resistant Common Ragweed.
  • Applications of glyphosate with heavy dew on the leaves may reduce activity.

Ethofumesate/Nortron Will Maximize Resistant Weed Population Control:

  • Ethofumesate/Nortron applied preemergence or preplant-incorporated will enhance the control of Waterhemp, Kochia, Lambsquarters, other pigweed species, Ladysthumb, Wild Buckwheat and Eastern Black Nightshade and proactively manage against glyphosate-resistant weeds.
  • Apply Nortron/Ethofumesate to the soil at 3 to 7.5 Pt/A, using the lowest rate when glyphosate-susceptible weeds are known to exist in a field and higher rates when glyphosate-resistant weeds exist, especially Kochia.
  • Apply Ethofumesate/Nortron postemergence once at 12 fl. oz./A, twice at 6 fl oz./A , or three times at 4 fl oz. /A with glyphosate in Roundup Ready® sugarbeet to improve weed control, especially in glyphosate-resistant populations. The number of applications will be determined by the 90 day preharvest interval.

  • Consider Ethofumesate/Nortron with Betamix and glyphosate.

579

New Sprayer Technology is available to adjust pressure, speed, and droplet size on the go to maximize weed control and reduce drift.

Addition of Betamix to Glyphosate will improve control of resistant Kochia and Waterhemp. Addition of 4 oz. of Ethofumesate/Nortron may further enhance Kochia & Waterhemp control.