• List of Herbicides

  • WSSA-Herbicide Site of Action (SOA) Classification List (last modified: 5/5/2021)
  • Common and chemical names approved by WSSA

• Information for Submitting New Herbicide Site of Action/Classification

  • Guidelines for submitting an Herbicide Site of Action
  • Guidelines for requesting new herbicide classification

Chemical Structures

Select a chemical from the list to view it’s structure. Click here to download a zipped file (880KB) with all structures in wmf format.

These structures have been provided by Bill Ahrens. They may be used for educational uses. If you would like a structure that is not listed, please contact Bill at chucao@softhome.net.

Photography of Herbicide Effects on Plants

These time-lapse photography videos show the effects of various herbicides on plants. The videos were originally prepared by Larry Burrill and Jerry Hill at Oregon State University and were further modified for digital format and made available for public use by D. R. Pike.

This information is copyrighted and may not be reproduced without the express permission of Oregon State University. For full video and information contact Oregon State University.

The movies are in AVI format, and will require a video player, such as Microsoft Windows Media Player, or similar.

POSTEMERGENCE APPLICATIONS (POST)

• 2,4-D on Tomato (4.7M)
• Clopyralid on Canada Thistle (4.6M)
• Paraquat on Bean (5.7M)
• Paraquat on Corn (4.6M)
• Fluazifop-butyl on Soybean and Oat (5.2M)
• Fluazifop-butyl on Cotton and Johnsongrass (5.0M)
• Sethoxydin on Soybean and Oat (5.0M)
• Diclofop-methyl on Wheat and Oat (4.8M)
• Glyphosate on Cowpea (5.0M)
• Glyphosate on Barley and Oat (5.2M)
• Atrazine on Cocklebur (4.2M)
• Chlorsulfuron on Sugarbeet (3.8M)
• Chlorimuron-ethyl on Soybean and Cocklebur (5.1M)

PREEMERGENCE APPLICATIONS (PRE)

• Atrazine on Oat (4.9M)
• Trifluralin on Oat Roots (5.4M)
• Metolachlor on Oat (5.0M)

PREPLANT APPLICATIONS (INCORPORATED WITH IRRIGATION)

• EPTC on Oat (2.8M)
• EPTC plus Safener on Corn and Sudangrass (4.9M)
• Chlorsulfuron on Bean (5.0M)