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IMPACT Herbicide

What is IMPACT herbicide?

IMPACT is a broad spectrum, systemic, low use rate postemergence herbicide for selective control of broadleaf weeds and grasses in field corn, seed corn, sweet corn and popcorn.

How does IMPACT herbicide work?

IMPACT contains the new active ingredient "topramezone". Topramezone inhibits plants' HPPD enzyme resulting in secondary effects on plant membrane structure and carotenoid pigment formation. Without these pigments, exposure to sunlight damages chlorophyll and susceptible weeds are killed.

What broadleaf weeds will IMPACT herbicide control?

IMPACT herbicide will provide postemergence control of major broadleaf weeds most common in corn such as velvetleaf, cocklebur, pigweed, waterhemp, lambsquarters and ragweed, including either triazine or ALS resistant biotypes.

Does IMPACT herbicide control grasses?

Yes, IMPACT herbicide provides control of several of the most common grass weed prlems in corn including giant foxtail, green foxtail and crabgrass. When a variety of well established grass species are present at the time of application combinations with a postemergence grass herbicides is recommended. AMVAC refers to the control and suppression of IMPACT on grass weeds as GrassAssist™. in corn including giant foxtail, green foxtail and crabgrass. In addition it allows flexibility in rotational cropping for major cropping practices. See specific guidelines for crop rotation in Federal and supplemental labels

Will IMPACT herbicide control grasses?

Yes, IMPACT herbicide has a high level of activity against several grass species, including giant foxtail, the most common grass problem in corn. However, combinations with postemergence grass herbicides will be recommended when a variety of well established grass weeds is present at application time. AMVAC refers to the control and suppression of IMPACT on grass weeds as GrassAssist™.

How may IMPACT herbicide fit into my corn weed control program?

IMPACT herbicide can be used to power the postemergence segment that follows a preemergence residual herbicide(s) in a two-pass program or may be utilized as a total post weed control program in tank mixtures with post grass herbicides and/or residual herbicides.

What are the IMPACT herbicide use rates?

IMPACT herbicide will be applied at very low use rates of 0.75 fluid ounce or less per acre.

When may applications of IMPACT herbicide be made?

IMPACT herbicide features a wide window for application timing; anytime after corn emergence until 45 days before harvest. Best agronomic practices and most effective performance will typically be achieved when applications are made to weeds in the early to mid post window (6" to 12" corn/2" to 6" weeds) before weeds compete with the corn crop.

Does AMVAC recommend IMPACT herbicide in tank mix programs?

Yes, standard use of IMPACT herbicide will most often include combinations with low rates of atrazine for maximum performance and value. Numerous other tank mixtures are labeled for use to provide producers with a variety of options and recommendations depending on the target weed spectrum.

What spray additives can be used with IMPACT herbicide?

Standard use rates of methylated seed oil (MSO) or crop oil concentrate (COC) plus a nitrogen source from UAN, AMS, or 10-34-0 fertilizer is recommended to maximize performance. When tank mixing refer to partner product label for adjuvant use with that particular product.

Is IMPACT herbicide registered for use on transgenic corn hybrids?

IMPACT herbicide is labeled for use on Roundup Ready® and LibertyLink® and Clearfield® hybrids, as well as on hybrids containing traits for insect management.

Does IMPACT herbicide use restrict grower options for insecticide use?

IMPACT herbicide offers exceptional corn tolerance and will allow flexibility with all current soil and foliar applied insecticide programs.

Does IMPACT herbicide limit rotational cropping flexibility?

IMPACT herbicide use will allow flexibility in rotational cropping for major cropping practices. Specific directions for crop rotation are addressed in the label.

How is IMPACT herbicide formulated?

IMPACT herbicide contains 2.8 pounds active ingredient (topramezone) per gallon in a suspension concentrate (SC) formulation.

How is IMPACT herbicide packaged?

IMPACT is packaged in 30 fluid ounce containers, with twelve containers per case and nine cases per pallet.

What are the key features and benefits of IMPACT herbicide?

IMPACT offers more in postemergence weed control; a broadleaf and grass weeds including those tough to control weeds or biotypes resistant to glyphosate, ALS and atrazine, , exceptional margin of crop selectivity, and low use rates. IMPACT herbicide provides corn producers new opportunities and advantages, and offers specialty corn growers a new level of control and superior crop safety.

What are the primary competitor products to IMPACT herbicide?

IMPACT herbicide combines excellent performance on the major broadleaf weeds and grasses in corn with outstanding crop safety. When used in a program approach for weed control, IMPACT herbicide may replace other standard pre and postemergence products.

What is the price of IMPACT herbicide?

IMPACT herbicide is priced competitively in the postemergence corn herbicide market.

How does AMVAC distribute IMPACT herbicide?

AMVAC has good relationships with distributors and retailers in the corn market due to our existing SmartBox® and corn soil insecticide business. IMPACT is offered through select distribution partners who will in turn sell to retailers, custom applicators and growers.

Where does AMVAC have license rights to sell IMPACT herbicide?

AMVAC has acquired exclusive rights for developing and marketing IMPACT herbicide in the United States and Canada.

Will AMVAC sell private label or premixes with IMPACT herbicide?

AMVAC is exploring all options in evaluating the best positioning of the product and would be open to selling private label or premixes.

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