is part of the Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them. Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

  • American Agriculturist
  • Beef Producer
  • Corn and Soybean Digest
  • Dakota Farmer
  • Delta Farm Press
  • Farm Futures
  • Farm Industry news
  • Indiana Prairie Farmer
  • Kansas Farmer
  • Michigan Farmer
  • Missouri Ruralist
  • Nebraska Farmer
  • Ohio Farmer
  • Prairie Farmer
  • Southeast Farm Press
  • Southwest Farm Press
  • The Farmer
  • Wallaces Farmer
  • Western Farm Press
  • Western Farmer Stockman
  • Wisconsin Agriculturist
herbicides

Herbicide Labels Include Standardized MOA Labeling

Herbicide labels now include a standardized system to inform users of the product’s mechanism of action (MOA). A box labeled ‘Herbicide Group’ is present near the top of the label. The number in the box represents MOA of the active ingredient, based on a system developed by the Weed Science Society of America. Premixes containing more than one mode of action will have multiple numbers listed. An example of the new logo is in the photo gallery to the left.

The intent of this information is to simplify development of herbicide programs that reduce the likelihood of selecting herbicide resistant weeds. In production systems relying largely on herbicides for weed management, using herbicides with different MOAs is the primary means of managing resistance.

Generally, the greater number of MOAs used, the less selection pressure placed on weeds.  However, designing an integrated program is not as simple as randomly adding MOAs. The different MOAs used in the program must have good activity on the important weeds in the field to successfully reduce selection pressure. Following are a few examples where the inclusion of an herbicide in a system relying on glyphosate in Roundup Ready crops would provide little benefit in terms of managing resistance for specific weeds.

  • A Group 2 herbicide would provide little benefit for waterhemp since most waterhemp is resistant to these herbicides.
  • A Group 15 herbicide would provide little benefit for giant ragweed or other large-seeded broadleaves due to its poor activity on these weeds.
  • Tankmixing low rates ( less than 0.75 lb.) of atrazine (Group 5) with glyphosate or other herbicides.

 

The new labeling system eliminates the need for farmers, consultants and suppliers to learn the MOA of all the active ingredients used in Iowa agriculture. However, to use the information properly, users must still know the activity of the individual herbicides on the weeds present in the field to insure that the target weeds are being affected by multiple MOAs.

You can download the Mechanism of Action document from the Weed Science Society of America as a PDF.

TAGS: Regulatory
Hide comments

Comments

  • Allowed HTML tags: <em> <strong> <blockquote> <br> <p>

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.
Publish