The library · Herbicide
Metsulfuron
A long-standing sulfonylurea for broadleaf weeds in cereals, pasture and chem-fallow, and a common low-rate partner.
- Group
- Herbicide Group 2
- Family
- SUs, IMIs, TPs and SCTs
- Formula
- C14H15N5O6S
- Molar mass
- 381.37 g/mol
- You may know it as
- Ally
- In Canada
- Several generics
Structure: PubChem CID 52999
How it kills
ALS / AHAS inhibitors
Blocks the enzyme that makes three key amino acids, so the plant can no longer build protein.
Growth stops first. Yellowing and death come slowly, sometimes over weeks.
Taken in by the leaf, then carried with sugars down to the roots and up to the growing points.
Where it fits
In the season.
Commonly used on
- Broadleaf weeds
- Perennials
- Cereals
Good to know
- Use rates are very low, so sprayer clean-out matters.
- Soil pH and dry conditions can stretch re-cropping intervals.
- Saskatchewan assumes all kochia is Group 2 resistant.
- The most resistance-prone group on the Prairies. Kochia, wild oats, cleavers and many others have Group 2 resistant biotypes.
Same group, same mode of action
