From labels and weed guides
Group 2 herbicides for horseweed in barley
There are 3 Group 2 active-ingredient groups rated good or excellent for horseweed in barley, with products labeled for barley.
Group 2 mode of action (MOA) options
Group 2 is a herbicide mode of action (MOA) group. Treat it as one resistance-management check, not as the whole program.
Every listed product is labeled for barley. Ratings are shown when each weed guide that rates this weed stays at good or excellent for the active-ingredient group. If a guide gives a range, the weaker end of the range has to be good or excellent.
Based on 3 weed guides, 3 active-ingredient groups are rated good or excellent for horseweed in barley.
| Example product | Active ingredients | MOA group | Ratings checked |
|---|---|---|---|
| Ally XP EPA 279-9575; same active ingredients on 10 other branded products | metsulfuron-methyl | 2 | WinField Crop Protection 2026, small grains: G (PDF) |
| Peak EPA 100-763; same active ingredients on 1 other branded product | prosulfuron | 2 | Ms Weed Guide 2025, ms small grain: G (PDF) |
| Quelex EPA 62719-661 | florasulam and halauxifen-methyl | 2, 4 | Ms Weed Guide 2025, ms small grain: E (PDF); ND Weed Guide 2026: G-E (PDF); WinField Crop Protection 2026, small grains: E (PDF) |
Rating legend: E=excellent, G=good, F=fair, P=poor, N=no control. A range such as G-E means the guide gives a range; 'a' after a rating (e.g., Ga) means the guide assumes its recommended additive.
Build the full program
Check crop, timing, state, resistance, and rotation in one plan before you make a recommendation.
Sources
Data from current labels and weed guides. Last source update: 2026-07-14.