Giant ragweed in Tennessee is the latest weed to be added to the list of glyphosate-resistant weeds found on the International Survey of Resistant Weeds Website. Other states with resistant giant ragweed include Arkansas, Indiana, Kansas, Minnesota and Ohio.

According to Delta Farm Press, the resistant populations were discovered in cotton and soybeans, in counties adjacent to the Mississippi River. To control giant ragweed, Larry Steckel, a row crop specialist with the University of Tennessee, recommends using a preplant herbicide and coming back with a good residual like Dual Magnum® or Reflex®. Unlike other parts of the Midwest, giant ragweed in Tennessee is mainly found  on field edges or in ditches, and Steckel would prefer it remain there.

Giant ragweed can cause huge yield deficits if left to compete with the crop. In Indiana and Ohio, glyphosate-resistant giant ragweed extends to 24 counties in the two states, and continues to grow. Minnesota also recently confirmed the weed resistant to glyphosate, as well as waterhemp. Kansas and Arkansas have also confirmed resistance.

The recent confirmation in Tennessee could only be the tip of the iceberg. According to the experts, glyphosate resistance could explode this year in all parts of the U.S. Giant ragweed is not a desirable weed to have to compete with, regardless of resistance concerns.

If you haven’t already put a management plan in place, now is the time to do it. For an easy, personalized management plan, visit www.resistancefighter.com/solutions to visit the Resistance Fighter Solutions Module. For more information, you can also visit the following:

Why You Don’t Want Glyphosate-resistant Giant Ragweed in Your Field

Effective Weed Management in Soybeans – Should I Use a Residual?

Weeds to Watch: Giant Ragweed

A Look at Giant Ragweed: Challenges and Solutions

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