Chapter 12: Herbicide Discovery and Classification
12.10 Examples of Classification System
In this section, we will demonstrate how the classification system works to describe herbicides. Here is one example that uses mode of action followed by site of action.
| Category | Example |
| Mode of Action | Lipid Synthesis Inhibition |
| A. Site of Action | A. Acetyl CoACarboxylase (ACCase) inhibition |
| 1. Chemical Family | 1. Aryloxyphenoxypropionates |
| Common Name | Quazilofop-P – Assure II – F |
Here is another example that uses mode of action followed by chemical family. If we work our way back up through the classification system we see that the product Assure II is absorbed foliarly, its common name is quazilofop-p, the chemical family for Assure II is the aryloxyphenoxypropionates. This herbicides site of action is the ACCase enzyme and that Lipid Synthesis Inhibition is the mode of action for Assure II.
| Category | Example |
| Mode of Action | Amino Acid Synthesis Inhibitors |
| Chemical Family | Sulfonylureas |
| Common Name (Trade Name) | Halosulfuron (Permit) |
| Site of Action | Acetolactate synthase enzyme (ALS) |
In this example, we can find out that the herbicide, Permit, has the active ingredient halosulfuron, belongs to the sulfonylurea chemical family and works by amino acid synthesis inhibition via the acetolactate synthase enzyme or ALS. Depending on the source of the classification scheme the hierarchy may be denoted using roman numerals, letters, and numbers or some combination of all three or no markings whatsoever. The denotations (numerals, letters, etc) are not very important and once you grasp the meanings of the terms and how they fit into the system then you will better understand herbicide classification.