From labels and weed guides
Best herbicides for knotweed in field corn
For knotweed in field corn, the weed guides list 14 active-ingredient groups rated good or excellent, after checking that the products are labeled for field corn.
Knotweed control in field corn
Every listed product is labeled for field corn. 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 1 weed guide, 14 active-ingredient groups are rated good or excellent for knotweed in field corn, showing the top 12 below.
| Example product | Active ingredients | MOA group | Ratings checked |
|---|---|---|---|
| AAtrex 4L EPA 100-497; same active ingredients on 31 other branded products | atrazine | 5 | WinField Crop Protection 2026, corn post: G (PDF) |
| Actylis Metribuzin EPA 2749-660; same active ingredients on 31 other branded products | metribuzin | 5 | WinField Crop Protection 2026, corn post: E (PDF) |
| Comet EPA 71368-87; same active ingredients on 8 other branded products | fluroxypyr 1-methylheptyl ester | 4 | WinField Crop Protection 2026, corn post: G (PDF) |
| Broclean EPA 34704-891; same active ingredients on 5 other branded products | bromoxynil | 6 | WinField Crop Protection 2026, corn post: G (PDF) |
| COLT AS EPA 34704-1019; same active ingredients on 5 other branded products | clopyralid and fluroxypyr 1-methylheptyl ester | 4 | WinField Crop Protection 2026, corn post: G (PDF) |
| Distinct EPA 7969-150; same active ingredients on 2 other branded products | dicamba and diflufenzopyr | 4, 19 | WinField Crop Protection 2026, corn post: E (PDF) |
| Double Header EPA 34704-1099; same active ingredients on 2 other branded products | acetochlor and mesotrione | 15, 27 | WinField Crop Protection 2026, corn post: G (PDF) |
| Daikon EPA 91234-217; same active ingredients on 1 other branded product | dicamba and halosulfuron-methyl | 2, 4 | WinField Crop Protection 2026, corn post: G (PDF) |
| Peak EPA 100-763; same active ingredients on 1 other branded product | prosulfuron | 2 | WinField Crop Protection 2026, corn post: G/E (PDF) |
| Acuron EPA 100-1466 | atrazine, bicyclopyrone, mesotrione, and metolachlor | 5, 15, 27 | WinField Crop Protection 2026, corn post: G (PDF) |
| Acuron Flexi EPA 100-1568 | bicyclopyrone, mesotrione, and metolachlor | 15, 27 | WinField Crop Protection 2026, corn post: G (PDF) |
| DiFlexx DUO EPA 264-1184 | dicamba and tembotrione | 4, 27 | WinField Crop Protection 2026, corn post: 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.
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Sources
Data from current labels and weed guides. Last source update: 2026-07-14.