Choosing The Path Of Least Resistance

While triazine resistance has leveled off, weed resistance to new chemistries is offsetting this trend.

With herbicide-resistant weeds on the increase and no new chemistries on the horizon, soybean farmers — and especially no-tillers — must carefully review their weed-control options, according to a panel of four field agronomists at the recent 2003 National No-Till Conference in Indianapolis, Ind.

They advised:

  • Use tankmixes or premixes of herbicides with different modes of action.
  • Avoid no-tilling crops that are resistant to the same herbicide back to back.
  • Stick with the resistance management strategy that makes the most economic sense for your operation.

“Herbicide-resistant biotypes are increasing every year,” says David Lamore, senior technical service representative for Bayer CropScience at Bryan, Ohio. “You have to choose a path of least resistance.” Lamore notes that although occurrence of triazine-resistant weeds is leveling off as the use of triazine herbicides has, the appearance of resistance to other chemistries offsets this trend.

Glyphosate Resistance.

The big news is confirmation of glyphosate-resistant marestail, says Dave Ruen, Dow AgroSciences customer agronomist at Lanesboro, Minn. He says research presented at the recent meeting of the North Central Weed Science Society in St. Louis, Mo., documents the existence of resistant marestail in the Delmarva Peninsula, New Jersey, Kentucky, west Tennessee, southern Indiana and Ohio. Without sound resistance management, the new weed type could quickly spread to other areas.

“Glyphosate has been used on tens of millions of acres, both as a burndown and in-crop,” Ruen says. “Now we’re seeing a pattern of resistance developing similar to the ALS inhibitors.” Lambsquarters, another problem weed in Roundup…

To view the full article, please subscribe or login.
 Premium content is for our Digital and Premium subscribers. Please purchase a subscription to get access to all No-Till Farmer content and archives.

Top Articles

Current Issue

NTF_July_0718_198w.jpg

No-Till Farmer

Get full access NOW to the most comprehensive, powerful and easy-to-use online resource for no-tillage practices. Just one good idea will pay for your subscription hundreds of times over.

View More

Must Read Free Eguides

Download these helpful knowledge building tools

View More
Top Directory Listings