S-Metolachlor

Type: Herbicide

Mode of Action: 

• Group 15: Very long-chain fatty acid (VLCFA) synthesis inhibitors

Common Product Names: Dual Magnum, Brawl, Medal

What is it?

S-Metolachlor is a selective, systemic herbicide commonly used in pre-emergent applications. It belongs to the chloroacetanilide family of herbicides and is known for its effectiveness in controlling a broad spectrum of annual grasses and certain broadleaf weeds. S-Metolachlor is most effective when applied as a pre-emergent herbicide. It should be applied before weed seeds germinate, typically in the early spring or before planting. The effectiveness of S-Metolachlor can often be seen within days to a couple of weeks, as weed seeds fail to emerge or young seedlings die off. Depending on the application rate and environmental conditions, S-Metolachlor can provide residual weed control for up to 4-8 weeks.

How does it work?

S-Metolachlor is absorbed primarily through the shoots and roots of emerging weed seedlings. Once inside the plant, it interferes with cell division and elongation by inhibiting the synthesis of key fatty acids. This disruption prevents the weed from developing normally, leading to its death before it can establish and compete with crops.

Benefits

• Pre-Emergent Action: By preventing weed seed germination, S-Metolachlor helps maintain a clean field, reducing the competition for resources like nutrients, water, and sunlight.
• Long Residual Activity: S-Metolachlor offers long-lasting residual control, often providing weed suppression for several weeks after application. This reduces the need for multiple herbicide applications within a growing season.