ImpactRegistered until: December 31, 2020
Amvac Chemical - Herbicide
28141

Herbicide controls weeds by inhibiting carotenoid biosynthesis (HPPD inhibitor).
Temperatures and moisture conditions for active plant growth are important for optimum IMPACT Herbicide activity.

DIRECTIONS FOR USE


FIELD CORN, SWEET CORN and SEED CORN (Hybrids and Inbred Lines)

IMPACT Herbicide is effective in post-emergence control of annual weeds in conservation tillage as well as in conventional production systems. Apply IMPACT Herbicide as a postemergence treatment to corn when weeds are actively growing. For optimal weed control, apply IMPACT Herbicide before the weeds exceed labeled leaf stages.
IMPACT Herbicide can be applied post-emergence on field corn, including imazethapyr tolerant corn (i.e., Clearfield®), glyphosate tolerant corn (i.e. Roundup Ready®) and glufosinate ammonium tolerant corn (i.e. LibertyLink® hybrids), sweet corn and seed corn (hybrids and inbred lines).
IMPACT Herbicide should be applied during favourable growing conditions for optimum crop tolerance and weed control. Crops under environmental stress are more likely to show injury from any herbicide application. Rarely, plants under these conditions treated with IMPACT Herbicide may show some transient bleaching of the portion of the leaves intercepting the spray application. These symptoms are transient and occur infrequently. Growth is not affected and normal plant appearance is seen within 1 to 2 weeks.
Field sprayer application: DO NOT apply during periods of dead calm. Avoid application of this product when winds are gusty. DO NOT apply with spray droplets smaller than the American Society of Agricultural and Biological Engineers® (ASABE®) medium classification. Boom height must be 60 cm or less above the crop or ground.
DO NOT apply by air.

Buffer zones:
Use of the following spray methods or equipment DO NOT require a buffer zone: hand-held or backpack sprayer and spot treatment.
The buffer zones specified in the table below are required between the point of direct application and the closest downwind edge of sensitive terrestrial habitats (such as grasslands, forested areas, shelter belts, woodlots, hedgerows, riparian areas and shrub lands) and sensitive freshwater habitats (such as lakes, rivers, sloughs, ponds, prairie potholes, creeks, marshes, streams, reservoirs and wetlands).
For tank mixes, consult the labels of the tank-mix partners and observe the largest (most restrictive) buffer zone of the products involved in the tank mixture and apply using the coarsest spray (ASABE) category indicated on the labels for those tank mix partners.

RESISTANCE-MANAGEMENT RECOMMENDATIONS

For resistance management, IMPACT Herbicide is a Group 27 herbicide. Any weed population may contain or develop plants naturally resistant to IMPACT Herbicide and other Group 27 herbicides. The resistant biotypes may dominate the weed population if these herbicides are used repeatedly in the same field. Other resistance mechanisms that are not linked to site of action, but specific for individual chemicals, such as enhanced metabolism, may also exist.
Appropriate resistance-management strategies should be followed.
To delay herbicide resistance:
Where possible, rotate the use of IMPACT Herbicide or other Group 27 herbicides with different herbicide groups that control the same weeds in a field.
Use tank mixtures with herbicides from a different group when such use is permitted.
Herbicide use should be based on an IPM program that includes scouting, historical information related to herbicide use and crop rotation, and considers tillage (or other mechanical), cultural, biological and other chemical control practices.
Monitor treated weed populations for resistance development.
Prevent movement of resistant weed seeds to other fields by cleaning harvesting and tillage equipment and planting clean seed.
Contact your local extension specialist or certified crop advisors for any additional pesticide resistance-management and/or integrated weed-management recommendations for specific crops and weed biotypes.

WEEDS CONTROLLED
For best performance on broadleaf weeds, spray before the weeds exceed the maximum leaf stage listed in the Application Directions table.
For best performance on grass weeds, spray before they exceed the maximum leaf stage listed in the Application Directions table.
IMPACT Herbicide is effective on biotypes of species listed that may be resistant to triazines or ALS herbicide products.
For field corn, IMPACT Herbicide may be tankmixed with AAtrex® 480, atrazine, glyphosate, atrazine plus glyphosate, or atrazine plus Frontier® Max™ herbicide to provide improved control of annual broadleaf and annual grass weeds.
For weed control in sweet corn and seed corn, IMPACT Herbicide must be tankmixed with atrazine. For full broad spectrum seasonal weed control, apply to sweet and seed corn following a pre-emergence application of a residual herbicide such as Frontier® Max™ herbicide.

APPLICATION DIRECTIONS

Merge® adjuvant, Hasten® NT spray adjuvant, Assist® oil concentrate or XA™ oil concentrate plus liquid fertilizer (UAN 28%) must be added to all applications of IMPACT Herbicide.
Uniformly apply with properly calibrated ground equipment using 200 L water per hectare.
Flat-fan nozzle tips are recommended for post-emergence applications. A spray pressure of 140-276 kPa is recommended.
Do not apply when wind speeds exceed 8 km/h or when drift near desirable plants is possible.

FIELD CORN

IMPACT Herbicide should be used as a broadcast ground treatment in tank mix with atrazine or with atrazine plus Frontier® Max™ herbicide for improved residual control of grass weeds.
IMPACT Herbicide may be used in tank mix with glyphosate or atrazine plus glyphosate for control of a broader spectrum of emerged grass and broadleaf weeds. Refer to the atrazine, glyphosate and Frontier® Max™ herbicide labels for precautions and restrictions.

SWEET CORN AND SEED CORN (Hybrids and Inbred Lines)

IMPACT Herbicide must be used as a broadcast ground treatment in tank mix with atrazine for improved weed control. For full broad spectrum seasonal weed control, apply following a preemergence application of a residual herbicide such as Frontier® Max™ herbicide. Refer to the atrazine label for precautions, restrictions and limitations.
Sweet and seed corn cultivars may vary in their tolerance to herbicides, including a tank mix of IMPACT Herbicide (topramezone) + atrazine (atrazine 480 herbicide or AAtrex Liquid 480 herbicide). Since not all sweet and seed corn cultivars have been tested for tolerance to a tank mix of topramezone + atrazine, first use should be limited to a small area of each cultivar to confirm tolerance prior to adoption as a general field practice. Additionally, consult your seed supplier for information on the tolerance of specific cultivars of sweet and seed corn to the tank mix of IMPACT Herbicide + atrazine.

TANK MIXES

When IMPACT Herbicide is used in combination with another herbicide, refer to the respective
label for rates, methods of application, proper timing, restrictions and precautions. Always use in accordance with the most restrictive label restrictions and precautions.
IMPACT Tankmix with atrazine (for use in field corn, sweet corn and seed corn – hybrids and inbred lines)
Apply IMPACT Herbicide when the corn is at the 1 to 7-leaf stage, broadleaf weeds are at the 1 to 8-leaf stage and grass weeds are at the 1 to 4-leaf stage.
Refer to the atrazine label for precautions, restrictions and limitations. Always use in accordance with the more restrictive label restrictions and precautions.

IMPACT Tank mix with Frontier Max Herbicide plus Atrazine
Apply when the corn is at the 1 to 3 leaf stage, broadleaf weeds are at the 1 to 8 leaf stage and grass weeds are at the 1 to 4 leaf stage.
Refer to the Frontier Max herbicide and atrazine labels for precautions, restrictions and limitations. Always use in accordance with the more restrictive label restrictions and precautions.

IMPACT Tankmix with Glyphosate
For control of emerged weeds, apply when the corn is at the 1 to 7 leaf stage, broadleaf weeds are at the 1 to 8 leaf stage and grass weeds are at the 1 to 4 leaf stage. Refer to glyphosate label for additional flexibility in weed stages at the time of application.
WARNING
Apply glyphosate on glyphosate tolerant field corn varieties only, i.e. varieties with the Roundup Ready gene. CORN VARIETIES WHICH ARE NOT DESIGNATED AS GLYPHOSATE TOLERANT or ROUNDUP® READY® WILL BE DAMAGED OR DESTROYED BY THIS TREATMENT.
Refer to the glyphosate label for precautions, restrictions and limitations. Always use in accordance with the more restrictive label restrictions and precautions.

IMPACT Tankmix with Glyphosate plus Atrazine
For control of emerged weeds, apply when the corn is at the 1 to 7 leaf stage, broadleaf weeds are at the 1 to 8 leaf stage and grass weeds are at the 1 to 4 leaf stage. Refer to glyphosate label for additional flexibility in weed stages at the time of application.
WARNING
Apply glyphosate on glyphosate tolerant field corn varieties only, i.e. varieties with the Roundup Ready gene. CORN VARIETIES WHICH ARE NOT DESIGNATED AS GLYPHOSATE TOLERANT WILL BE DAMAGED OR DESTROYED BY THIS TREATMENT.
Refer to the atrazine and glyphosate labels for precautions, restrictions and limitations.
Always use in accordance with the more restrictive label restrictions and precautions.

IMPACT Tank Mix with PROWL® H2O and AATREX 480 (for use in field corn)
For control of emerged weeds, apply when the corn is at the 1 to 4-leaf stage, broadleaf weeds are at the 1 to 8-leaf stage and grass weeds are at the 1 to 4-leaf stage.
Refer to the Prowl H2O and atrazine labels for precautions, restrictions, limitations, buffer zone and rotational re-cropping guidelines. Always use in accordance with the more restrictive label restrictions and precautions.
IMPACT® Herbicide may be used as a broadcast tank mix with PROWL H2O and AATREX 480 to control broadleaf weeds and annual grasses as follows. Apply in 200 L of water per hectare with a field sprayer.
PROWL H2O at 3.7L/ha plus
IMPACT Herbicide at 37mL/ha plus
AATREX 480 at 1.04L/ha plus
MERGE at 0.5% v/v , i.e. 5 litres per 1000 L spray solution or
HASTEN NT spray adjuvant at 0.5% v/v, i.e. 5 litres per 1000 L spray solution or
ASSIST at 1.25% v/v, i.e. 12.5 litres per 1000 L spray solution or
XA oil concentrate at 1% v/v, i.e. 10 litres per 1000 L spray solution
plus UAN at 1.25% v/v, i.e. 12.5 litres per 1000 L spray solution.

WEEDS CONTROLLED
The tank mix provides post emergence control of emerged weeds. Temperatures and moisture conditions for active plant growth are important for optimum herbicide activity.
Barnyard Grass, Common
Crabgrass(large and smooth)
Green Foxtail
Yellow Foxtail
Common Chickweed
Lamb's quarters 1
Green Pigweed 1
Redroot Pigweed 1
Green Smartweed
Common Ragweed
Wild Buckwheat
Velvetleaf 2
Pennycress
Wild Mustard
Lady's Thumb
1 Includes triazine resistant biotypes.
2 Early post-emergence application only up to the 3-leaf stage of corn.

SPRAY ADDITIVES
For best adherence and foliar uptake, IMPACT Herbicide may require the addition of spray additives to the spray solution. Consult the Application Direction tables for rates and recommendations.

MIXING INSTRUCTIONS AND ORDER
IMPACT Herbicide Tank Mixes:
Add dry material first for proper dispersion.
1. Fill sprayer 1/2 full with clean water and agitate.
2. Add dry tank mix partners into the spray tank and agitate.
3. Add IMPACT Herbicide and thoroughly mix.
4. After the IMPACT Herbicide has visibly dispersed, add any liquid herbicide tank mix partners.
5. Add either Merge adjuvant, Hasten NT spray adjuvant, Assist oil concentrate, or XA oil concentrate followed by liquid fertilizer (UAN 28%), with the exception of glyphosate tankmixes.
6. While agitating, fill the remainder of the tank with water up to the proper level.

CROP HARVEST
Do not apply IMPACT Herbicide within 45 days of corn harvest (silage, fodder or grain).
Do not graze or feed treated corn forage, silage, fodder or grain for at least 45 days after an application of IMPACT Herbicide.
Treated seeds grown for seed production are not to be fed to livestock.

ROTATIONAL CROPPING
In the event of crop failure in fields treated with IMPACT Herbicide, only field corn can be replanted as a rescue crop. A second application of IMPACT Herbicide cannot be made in the rescue crop.
Fields treated with IMPACT Herbicide can be seeded to winter wheat at a minimum four months after application and can be seeded to spring wheat, field corn, navy (white) bean, soybean, pea and alfalfa the following year.
Conduct a field bioassay (a test strip grown to maturity) the year before growing any other crop.
If using IMPACT Herbicide in tank mixtures, always refer to the tank mix partner’s product label for any additional recropping restrictions.

CropsBBCHRegistred normPreharvest Interval
Corn, maize0 - 037 - 3745