Proven Power. Lasting Results.

IMPACT CORE® is a postemergence corn herbicide that controls grass and broadleaf weed with punishing takedown and lasting residual.

IMPACT CORE Herbicide delivers trusted takedown of herbicide-resistant grasses and broadleaf weeds such as waterhemp, Palmer amaranth, and giant ragweed.


The proven takedown power of topramezone, the active ingredient in Impact® Herbicide, combined with an industry-leading level of acetochlor provides reliable residual control you can trust.

Product Benefits


Trusted takedown of herbicide-resistant grasses and broadleaf weeds1 such as waterhemp, Palmer amaranth and giant ragweed. Reliable residual control of herbicide-resistant grass and broadleaf weeds2 has been the hallmark of acetochlor performance in corn weed control.


Delivers control across a wide range of field conditions, weed densities and in either a one or two-pass application system.


Austin, MN – Untreated

The field was like a carpet of weeds at application.

Austin, MN – Treated

Pre – Acetochlor containing premix.
Post – IMPACT CORE® at 36 oz. + glyphosate + atrazine + adjuvants.
Waterhemp control was as good, if not better than the standard treatment and the residual seems better.

Download Materials


Technical Bulletin

Product Sheet

1Except for group 27 resistant weeds

2Except for group 15 resistant weeds

AMVAC’s website is updated regularly and may not contain the most current EPA registered product label or safety data sheet. Please contact your local AMVAC representative to confirm you have current product information. It is the sole responsibility of the end user to read and follow product use directions and to comply with all federal, state or local laws. This product may not be registered in all states and users are advised to confirm that the product is registered in all states of intended use. Important: Always read and follow label instructions. See label for listed weeds and pests.

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