Fieldstar WDG

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Fieldstar WDG Herbicide is a selective herbicide for the control of certain annual broadleaved weeds in field corn. Fieldstar WDG may be applied surface preplant, preplant incorporated, or preemergence in field corn. Absorption of Fieldstar WDG occurs through both foliage and root uptake. Susceptible weeds exposed to Fieldstar WDG stop growing and either die or remain non-competitive with the crop. Because uptake and translocation of Fieldstar WDG involves uptake by both roots and/or foliage, adequate soil moisture is necessary for optimal activity.



Do not use in greenhouses.
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.
As this product is not registered for the control of pests in aquatic systems, DO NOT use to control aquatic pests. DO NOT contaminate irrigation or drinking water supplies or aquatic habitat by cleaning of equipment or disposal of wastes.
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 Engineers (ASAE) medium classification. Boom height must be 60 cm or less above the crop or ground.
DO NOT apply by air.
Soil Insecticides: Organophosphate granular insecticides must not be used on a crop to be treated with Fieldstar WDG. Serious crop injury may occur.
Do not apply when weather conditions favour drift to non-target sites.

To minimize spray drift to nontarget areas:
1. Do not use nozzles that produce a fine spray droplet.
2. Minimize drift by using sufficient spray volume to ensure adequate coverage with large droplet size sprays.
3. Keep ground-driven spray boom as low as possible above the target surface.
4. Spray when conditions are calm or wind speed is less than 10 km/hr.

Adequate soil moisture is required for optimum herbicide activity of Fieldstar WDG. Surface preplant, or preemergence applications of Fieldstar WDG require an activating rainfall which moistens the soil to a depth of at least 5 cm.
Do not apply when air temperature is near freezing or when freezing conditions are expected for several days following time of application.
Extended cold, wet conditions (soil temperatures below 10°C for extended periods) or abnormally high soil moisture conditions during emergence and early crop development can cause Fieldstar WDG injury symptoms on corn such as temporary yellowing of the leaves and/or crop stunting. Corn will quickly outgrow these symptoms once normal growing conditions resume.
Over-application may result in crop injury or rotational crop damage from soil residues.
Conditions such as seedling disease, cold weather, excessive moisture, compacted soils (such as along headlands) or eroded knolls or hillsides may increase the possibility of crop injury from Fieldstar WDG.
Make only 1 application per year. 
Do not apply Fieldstar WDG to sweet corn, seed corn or popcorn. 
Recommended corn planting depth is at least 4 cm for fields treated with Fieldstar WDG. 
Do not apply to areas where the soil pH is less than 5.9 or greater than 7.8. 
Do not apply to areas where the soil organic matter is less than 2.0%.
Do not apply to peat or muck soils or where the soil organic matter is greater than 5%. 
Crop residues from treated areas cannot be used for composting or mulching on ground where susceptible crops may be grown the following season. To promote herbicide decomposition plant material should be evenly incorporated into the soil. Adequate moisture is also required to promote breakdown of plant residues which contain clopyralid.
Do not repeat application of Fieldstar WDG to the same field in the following season as there is a potential for residue build-up

Sprayer Clean-up
To avoid injury to or exposure of non-target crops, thoroughly clean and drain spray equipment used to apply Fieldstar WDG after use. Cleaning should occur as soon as possible after Fieldstar WDG application. All rinsate material should be collected in a suitable container and disposed of according to label directions (i.e., applying it to cropland to be planted to crops recommended on this label) or in a locally approved manner (see Disposal section). Spray equipment used to apply Fieldstar WDG should be cleaned after use by the following procedure:
1. Drain the sprayer tank.
2. Hose down the interior surfaces of the tank. Flush tank, hoses, boom and nozzles with clean water for 10 minutes. Fill the tank with water and recirculate for 15 minutes. Spray part of the mixture through the hoses, boom and nozzles and drain the tank.
3. Remove the nozzles and screens and clean them separately.
4. If the spray equipment will be used on crops other than field corn, repeat steps 1 and 2 again and thoroughly wash the spray mixture from the outside of spray tank and the boom.

When tank mixing with other herbicides, follow the most restrictive crop rotation guidelines on the label of each product used. The table below outlines the interval required between the application of Fieldstar WDG and the seeding of rotational crops.

In extremely dry conditions (less than 38 cm rainfall in the 10 months following application of Fieldstar WDG) the rotation interval for soybeans should be extended to 22 months. A field bioassay should be conducted before planting other crops not listed above.
A successful field bioassay means growing to maturity a test strip of the crop(s) intended for production the following year.

Field Bioassay
Using typical tillage, seeding practices, and timings for the particular crop, plant several strips of the desired crop across the field previously treated with Fieldstar WDG. Plant the strips perpendicular to the direction Fieldstar WDG was applied. The strips should also be located so that different field conditions are encountered, including soil texture, drainage and compacted areas. If the crop does not show visible symptoms of injury or stand reduction, the field can be seeded with the test crop in the growing season following the bioassay. If visible injury or stand reduction occurs, the test crop should not be seeded and the bioassay must be repeated the next growing season.

Do not graze the treated corn crop prior to harvest for silage; sufficient data are not available to support this use.

DIRECTIONS FOR USE – Fieldstar WDG Applied Alone
Fieldstar WDG is for use on hybrid field corn in Eastern Canada only.

Surface Preplant
Application For no-tillage systems, Fieldstar WDG alone or in a tank-mix (see tank-mix table) may be applied up to 15 days before planting. To the extent possible, do not move treated soil out of the row or move untreated soil to the surface during planting or weed control will be diminished. Annual broadleaved weeds beyond the 2 leaf stage of growth will not be controlled by surface preplant applications.

Preplant Incorporated Application
Apply Fieldstar WDG alone or in a tank-mix (see tank-mix table) up to 15 days before planting. Incorporate Fieldstar WDG in a uniform manner with equipment set to work at a depth of 5 to 8 cm. Use a C or S shank field cultivator equipped with a levelling device such as harrows or rolling basket attachment. The cultivator must have a minimum of 4 rows of sweeps spaced at 18 cm or less intervals and staggered so that no soil is left unturned. Tandem discs may also be used providing the blades are less than 50 cm in diameter and spaced 18 cm or less apart. Equipment design including any drag attachments must be adequate to avoid soil ridging which may result in streaked or reduced weed control. Operate disc implements at 6 to 10 km/hr and cultivators at 10 to 13 km/hr.

Preemergence Application
Preemergence applications may be made in conventional tillage as well as reduced tillage, ridge tillage and no-till systems. Apply Fieldstar WDG alone or in a tank-mix (see tank-mix table) during (behind the planter) or after planting, but prior to crop or weed emergence. Adequate soil moisture is required for optimum herbicidal activity. Rainfall is necessary to move Fieldstar WDG into the weed germination zone.
Sufficient rainfall to moisten the soil to a depth of 5 cm is generally adequate. If adequate rainfall is not received within 7 to 10 days after a surface application, a shallow cultivation or use of a rotary hoe is recommended to control established weeds and move the herbicide into the weed germination zone. When adequate rainfall is received following dry conditions, activity on established weeds will depend on the weed species and the location of its root system in the soil.

Fieldstar WDG Herbicide Applied Alone
Fieldstar WDG may be applied alone for broadleaved weed control only as a surface preplant, preemergence, or preplant incorporated application.

Thorough mixing is required. To ensure a uniform spray mixture, continuous agitation is required during mixing and spraying. Apply spray mixture within 24 hours after mixing. If the product is allowed to settle, thoroughly agitate to resuspend the mixture before spraying.

Spray Preparation
Fieldstar WDG is a water dispersible granule formulation. Vigorous, continuous agitation during mixing, filling and throughout application is required for all tank-mixes. Sparger pipe agitators generally provide the most effective agitation in spray tanks. To prevent foaming in the spray tank avoid stirring or splashing air into the spray mixture. To prevent foaming during filling keep end of fill pipe below the surface of the liquid in the spray tank. The addition of an anti-foaming agent such as HaltTM may also reduce foaming.
The following method is recommended:
1. Fill the spray tank with 1/4 to 1/3 of the total amount of water or liquid fertilizer solution (28-0- 0 or 32-0-0) required for the load. 2. Start the agitation system.
3. Add the required amount of product into the spray tank while agitating. For applications in liquid fertilizer, add a slurry of Fieldstar WDG into the spray tank through a 20 to 35 mesh screen. (See Premixing Fieldstar WDG For Use With Liquid Fertilizer Solution (28-0-0, 32-0- 0) section below).
4. Continue agitation until product is completely dispersed.
5. Add tank-mix partner (if applicable) and allow to completely mix while continuing agitation.
6. Add non-ionic surfactant (if applicable).
7. Complete filling spray tank while continuing agitation system.
8. Before spraying, make sure the product is thoroughly mixed with water. Depending on the water temperature and the degree of agitation, the product should be completely dispersed within 5 minutes from the time it is added to the water.
If spraying and agitation must be stopped before the spray tank is empty, the materials may settle to the bottom. Settled materials must be resuspended before spraying is resumed. A sparger agitator is particularly useful for this purpose. Settled material may be more difficult to resuspend than when originally mixed. Line screens in the spray tank should be no finer than 50 mesh (100 mesh is finer than 50 mesh).

Premixing Fieldstar WDG For Use With Liquid Fertilizer Solution (28-0-0, 32-0-0)
The following premixing instructions must be followed when Fieldstar WDG is used in liquid fertilizer.
1. Fieldstar WDG should be premixed with water to form a slurry. For best results, a minimum of 0.5 L of water should be used to slurry each hectare rate (270 g) of Fieldstar WDG. Stir until the granules are dispersed.
2. Add the slurry to the spray tank through a 20 to 35 mesh screen as described in step 3 in Spray Preparation instructions above. Rinse the slurry container into the spray tank.  

Spray Application
Apply Fieldstar WDG in sufficient spray volume to provide uniform coverage using properly calibrated ground equipment. A total spray volume of 100 to 400 L/ha using low pressure (135 to 270 kPa) application is recommended. Maintain sufficient agitation in the sprayer tank during mixing and spraying to ensure a uniform spray mixture.

Fieldstar WDG may be tank mixed with other herbicides to control a broader spectrum of weeds. Refer to the following table for timing of application, weeds controlled and product rates. Refer to individual product labels for specific weeds controlled.

Use of the following spray methods or equipment DOES 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, wood lots, hedgerows, riparian areas and shrublands), 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 (ASAE) category indicated on the label for those tank-mix partners.

For resistance management, please note that Fieldstar WDG Herbicide is both a Group 2 and a Group 4 herbicide. Any weed population may contain plants naturally resistant to Group 2 and/or Group 4 herbicides. The resistant biotypes may dominate the weed population if these herbicides are used repeatedly in the same fields. Other resistance mechanisms that are not linked to site of action, but specific for individual chemicals, such as enhanced metabolism, may also exist. Appropriate resistancemanagement strategies should be followed.
To delay herbicide resistance:
Where possible, rotate the use of Fieldstar WDG Herbicide or other Group 2 and/or Group 4 herbicides within a growing season (sequence) or among growing seasons 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. To delay resistance, the less resistance-prone partner should control the target weed(s) as effectively as the more resistance-prone partner.
Herbicide use should be based on an integrated weed management program that includes scouting, historical information related to herbicide use and crop rotation, and considers tillage (or other mechanical control methods), cultural (for example, higher crop seeding rates; precision fertilizer application method and timing to favour the crop and not the weeds), biological (weedcompetitive crops or varieties) and other management practices.
Monitor weed populations after herbicide application for signs of resistance development (for example, only one weed species on the herbicide label not controlled). If resistance is suspected, prevent weed seed production in the affected area if possible by an alternative herbicide from a different group. Prevent movement of resistant weed seeds to other fields by cleaning harvesting and tillage equipment when moving between fields, and planting clean seed.
Have suspected resistant weed seeds tested by a qualified laboratory to confirm resistance and identify alternative herbicide options.
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.

NOTICE TO USER: This pest control product is to be used only in accordance with the directions on the label. It is an offence under the Pest Control Products Act to use this product in a way that is inconsistent with the directions on the label. The user assumes the risk to persons or property that arises from any such use of this product.

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Corn270 g