Challenger Herbicide

Manufacturer
Dow AgroSciences
Category
Herbicides
Registered until
2023-08-09
Registration number
29617
Active materials
Links

PRODUCT INFORMATION
Challenger Herbicide is a systemic, postemergence herbicide for the selective control of wild oats, volunteer tame oats, green foxtail, yellow foxtail, barnyard grass and Persian Darnel in spring wheat, durum wheat, winter wheat, barley, triticale, spring rye, winter rye, and selected forage grasses (except Timothy) grown for seed only.

DIRECTIONS FOR USE

Rates of Use
Apply Challenger Herbicide at 0.5 L/ha in 50-100 L/ha of water.
Note: Always add Turbocharge or Intake Adjuvant to the spray solution at a rate of 0.5 L per 100 L of spray mixture (0.5% v/v). Under adverse conditions, such as dense weed population, late weed growth stage, or poor environmental conditions apply 1.0% V/V of Intake Adjuvant (10 L Intake Adjuvant /1000 L spray mixture) The incorrect Turbocharge or Intake Adjuvant rate can result in unacceptable weed control or crop injury. See MIXING and SPRAYING INSTRUCTION sections.

Only one application per season is permitted.
Apply only when the potential for drift to areas of human habitation or areas of human activity such as houses, cottages, schools and recreational areas is minimal. Take into consideration wind speed, wind direction, temperature inversions, application equipment and sprayer settings.

Challenger Herbicide can be used on the following crops:


CEREAL CROPS: (Spring Wheat, Durum Wheat, Winter Wheat, Barley, Triticale, Spring Rye and Winter Rye) Challenger Herbicide can be used in all varieties of spring wheat (including Canada Western red spring, amber durum, soft white spring, extra strong and Canada prairie spring), red winter wheat, all 2 or 6 row varieties of barley (malting and feed varieties), all varieties of triticale, spring rye and winter rye.

Note: Tillered cereal crops may incur injury if applications are made within 48 hours of freezing temperatures. Non-tillering cereal crops which are exposed to temperatures of 4 C or less up to 48 hours before or after application may incur injury. Tank mixing Challenger Herbicide with a broadleaf weed herbicide under adverse conditions may increase severity of crop injury. Crops under stress from foliar diseases or low fertility are more susceptible to injury from Challenger Herbicide.

Do not use in tame oat crops. Avoid drift onto tame oat and corn crops.
Do not replant treated areas to tame oats or corn for at least 4 weeks after application.

In Eastern Canada Challenger Herbicide is to be used only for the control of w ild oats in spring wheat, winter wheat, durum wheat, barley and all varieties of triticale and spring and winter rye.

Minimum Interval to Harvest
Immature cereal crops may be grazed or cut for hay 16 days after treatment. Grain may be harvested 60 days after treatment. Mature straw may be fed to livestock. Do not feed or graze underseeded forage crops in the year of treatment, sufficient data are not available to support this use.

CEREAL CROPS UNDERSEEDED TO FORAGE LEGUMES: alfalfa, birdsfoot trefoil, sainfoin and clovers.

TANK MIXES OF CHALLENGER HERBICIDE WITH BROADLEAF WEED HERBICIDES
Challenger Herbicide alone will not control broadleaf weeds. For broad spectrum control of both annual grasses and broadleaf weeds, Challenger Herbicide can be tank mixed with a variety of broadleaf weed herbicides. Refer to the following table for details and additional guidance. Read the appropriate broadleaf herbicide label for information on broadleaf weeds controlled.
Tank Mixing Notes
1. Read and strictly adhere to the use directions and precautions on the label of the product(s) that is/are being tank mixed with Challenger Herbicide. Also note all environmental restrictions and guidance such as rain fastness and maximum spraying temperatures on the label of the other product(s) being tank mixed.
2. Do not tank mix with amine formulations of 2,4-D or with amine formulations of MCPA or with any other herbicide, insecticide, fungicide, fertilizer solution or adjuvant not recommended on the label as poor grass control and/or unacceptable crop injury may result.
3. With reduced water volumes, tank mixes with Buctril M, Thumper or Pardner may result in some initial injury in the form of "tip burn". This injury, how ever, will not have any adverse effect on crop maturity or yield.
4. Do not tank mix Challenger Herbicide with broadleaf herbicides when applying to cereal crops underseeded to forage legumes as the forages may be injured or killed.
5. Tank mixes with the high rate of Attain XC A Herbicide + Attain XC B Herbicide or high rate of Prestige XC Herbicide may cause temporary crop injury if applied before the 4 leaf stage, how ever, yield will not normally be affected.
These tank mixes may provide a lower level of wild oat control than Liquid Achieve SC Herbicide alone.
6. Temporary crop injury may occur with registered tank mixes, in particular 2,4-D Ester/dichlorprop products, under extreme weather conditions or when the crop is suffering from stress due to inadequate or abnormally high moisture levels, or extreme temperatures. Barley may be injured with tank mixes of 2,4-D Ester/dichlorprop and Buctril M plus MCPA.
7. Herbicides not listed on this label for tank mixing with Challenger Herbicide may be applied separately in sequence. Always apply Challenger Herbicide first and allow at least 7 days after the application of Challenger Herbicide before applying the other herbicide. Herbicides labelled for tank mixing with Challenger Herbicide may also be applied sequentially, either before or after application of Challenger Herbicide.

TANK MIXES OF CHALLENGER HERBICIDE WITH INSECTICIDES
Challenger Herbicide alone or in combination with Buctril M products or Pardner can be tank mixed with Matador120EC Emulsifiable Concentrate Insecticide or Decis Flow able for one pass weed and insect control. Always add Matador 120EC Emulsifiable Concentrate Insecticide or Decis Flow able to the spray tank after the herbicides but before adding Turbocharge or Intake Adjuvant.

Tank Mixtures
In some cases, tank mixing a pest control product with another pest control product or a fertilizer can result in biological effects that could include, but are not limited to: reduced pest efficacy or increased host crop injury. The user should contact Dow AgroSciences Canada Inc. at 1-800-667-3852 or www.dowagro.ca for information before mixing any pesticide or fertilizer that is not specifically recommended on this label. The user assumes the risk of losses that result from the use of tank mixes that do not appear on this label or that are not specifically recommended by Dow AgroSciences Canada Inc.

MIXING INSTRUCTIONS
Follow the mixing instructions below for adding Challenger Herbicide to the spray tank.
1. Only use sprayers in good running condition with high agitation. Ensure the sprayer and pre-mix tank is cleaned according to instructions on label of the product used prior to Challenger Herbicide. Use only clean water for the spray solution. Ensure that all in-line strainer and nozzle screens in the sprayer are 50 mesh or coarser. Screens of 80 mesh size or finer should not be used.
2. Begin to fill sprayer tank or premix tank with clean water, and engage agitator. Agitation must be continued throughout the entire mixing and spraying procedure.
3. When the sprayer or premix tank is three quarters full of water, add Challenger Herbicide. If more than 1 case of Challenger Herbicide is to be used, add the Challenger Herbicide from all cases prior to adding tank mixed products or Turbocharge or Intake Adjuvant.
4. If tank mixing, add the recommended product(s) next.
5. Lastly, add Turbocharge or Intake Adjuvant, and then continue to fill tank to desired level with water.

GROUND SPRAYING INSTRUCTIONS
1. Apply in a spray volume of 50-100 L/ha at a pressure of 275 kPa to ensure proper dispersion, spraying characteristics and performance of Challenger Herbicide.
2. Flat fan nozzles of 80 or 110 are recommended for optimum coverage. Do not use floodjet nozzles or controlled droplet application equipment. Nozzles may be angled forward 45 to enhance penetration of the crop and provide better coverage. Ensure that all in-line strainer and nozzle screens in the sprayer are 50 mesh or coarser. Screens of 80 mesh or finer should not be used.
3. Always ensure that agitation is continued until spraying is completed, even if stopped for brief periods of time. If the agitation is stopped for more than 5 minutes, re-suspend the spray solution by running on full agitation prior to spraying. Do not begin spraying until fully re-suspended.
Challenger Herbicidemust be sprayed within the same day of mixing.
4. When spraying is completed and prior to using other products, ensure the sprayer tank is thoroughly rinsed with clean water to remove any remaining Challenger Herbicide residues. Using a pressure washer and the addition of a detergent or Agral 90 to the rinse water will enhance removal of residues.

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 Engineers (ASAE) medium classification. Boom height must be 60 cm or less above the crop or ground.

AERIAL APPLICATION

Generic Aerial Application Label Instructions - Directions for Use
Apply only by fixed-wing or rotary aircraft equipment which has been functionally and operationally calibrated for the atmospheric conditions of the area and the application rates and conditions of this label.
Label rates, conditions and precautions are product specific. Read and understand the entire label before opening this product. Apply only at the rate recommended for aerial application on this label. Where no rate for aerial application appears for the specific use, this product cannot be applied by any type of aerial equipment.
Ensure uniform application. To avoid streaked, uneven or overlapped application, use appropriate marking devices.

Use Precautions
Apply only w hen meteorological conditions at the treatment site allow for complete and even crop coverage. Apply only under conditions of good practice specific to aerial application as outlined in the National Aerial Pesticide Application Manual, developed by the Federal/Provincial/Territorial Committee on Pest Management and Pesticides.
Do not apply to any body of water. Avoid drifting of spray onto any body of water or other non-target areas. Specified buffer zones should be observed.
DO NOT apply during periods of dead calm. Avoid application of this product when winds are gusty. DO NOT apply when wind speed is greater than 16 km/h at flying height at the site of application. DO NOT apply with spray droplets smaller than the American Society of Agricultural Engineers (ASAE) medium classification. To reduce drift caused by turbulent wingtip vortices, the nozzle distribution along the spray boom length MUST NOT exceed 65% of the wing or rotorspan.

Operator Precautions
Do not allow the pilot to mix chemicals to be loaded onto the aircraft. Loading of premixed chemicals with a closed system is permitted.
It is desirable that the pilot have communication capabilities at each treatment site at the time of application.
The field crew and the mixer/loaders must wear chemical resistant gloves, coveralls and goggles or face shield during mixing/loading, cleanup and repair. Follow the more stringent label precautions in cases where the operator precautions exceed the generic label recommendations on the existing ground boom label.
All personnel on the job site must wash hands and face thoroughly before eating and drinking. Protective clothing, aircraft cockpit and vehicle cabs must be decontaminated regularly.

AERIAL SPRAYING INSTRUCTIONS
1. Apply in a spray volume of 30 to 45 L/ha at a pressure of 140-275 kPa to ensure proper dispersion, spraying characteristics and performance of Challenger Herbicide.
2. Flat fan nozzles of 80 or 110 are recommended for optimum coverage. Do not use floodjet nozzles or controlled droplet application equipment. Ensure that all in-line strainer and nozzle screens in the sprayer are 50 mesh or coarser. Screens of 80 mesh size or finer should not be used.
3. Always ensure that agitation is continued until spraying is completed, even if stopped for brief periods of time. If the agitation is stopped for more than 5 minutes, re-suspend the spray solution by running on full agitation prior to spraying. Challenger Herbicide must be sprayed within the same day of mixing.
4. Do not apply Challenger Herbicide if the wind is more than 13 km/h. This will avoid spray drift onto non-target areas.
5. Do not spray Challenger Herbicide if tame oats are present in adjacent, downwind fields.
6. When spraying is completed and prior to using other products, ensure the sprayer tank is thoroughly rinsed with clean water to remove any remaining Challenger Herbicide residues. Using a pressure washer and the addition of a detergent or Agral 90 to the rinse water will enhance removal of residues.
7. DO NOT APPLY within 50 m of non-crop areas. This includes fish-bearing waters, wetlands (potholes, sloughs etc.) and wildlife habitat (hedgerows, rights of way, etc.).

RESISTANCE MANAGEMENT RECOMMENDATIONS
For resistance management, Challenger Herbicide is a Group 1 herbicide. Any weed population may contain or develop plants naturally resistant to Challenger Herbicide and other Group 1 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 Challenger Herbicide or other Group 1 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 resistancemanagement and/or integrated weed-management recommendations for specific crops and weed biotypes.
For further information or to report suspected resistance, contact Dow AgroSciences Canada Inc. at 1-800-667-3852 or at www.dowagro.ca.

Registered for culturesRatePreharvest Interval
Spring wheat0.5 l60
Winter wheat0.5 l60
Spring barley0.5 l60
Winter barley0.5 l60
Winter triticale0.5 l60
Spring triticale0.5 l60
Winter rye0.5 l60
Spring rye0.5 l60