SOYBEANS - ALL TILLAGE TYPES - PREEMERGENCE
Prefix Herbicide is a selective herbicide for the control or partial control of certain grass, broadleaf and sedge weeds in soybeans. Prefix Herbicide may be applied as a preplant surface, preplant incorporated, preemergence, or postemergence treatment.
MODE OF ACTION
Prefix Herbicide is a mixture of the active ingredients S-metolachlor and fomesafen. S-metolachlor is a biosynthesis inhibitor (Group 15 mode of action) preventing cell division in emerging weeds.
Fomesafen is a protoporphyrinogen oxidase inhibitor (Group 14 mode of action) leading to cellular membrane disruption and plant death.
A small amount of soil moisture is required to activate Prefix Herbicide following application. In areas of low rainfall, a preemergence application to dry soil should be followed with light irrigation of 0.25-0.5 inch of water. As with many surface-applied herbicides, weed control and crop tolerance may vary with rainfall and/or soil texture. If rainfall or irrigation within 7-10 days does not occur, cultivate uniformly with shallow tilling equipment such as a rotary hoe that will not damage soybeans.
Ground Spray Equipment: Apply Prefix Herbicide alone or in tank mixtures by ground equipment in a minimum of 10 gal. of spray mixture per acre, unless otherwise specified.
Use sprayers that provide accurate and uniform application. Calibrate the sprayer before use at the beginning of the season. For Prefix Herbicide tank mixtures with wettable powder or dry flowable formulations, screens and strainers should be no finer than 50-mesh.
Aerial Application: Apply Prefix Herbicide in water using a minimum spray volume of 5 gal./A. Avoid application under conditions where uniform coverage cannot be obtained or where excessive spray drift may occur. Make applications at a maximum height of 10 ft. above the soybeans with low-drift nozzles at a maximum pressure of 40 psi.
Avoid application to humans or animals. Flagmen and loaders should avoid inhalation of spray mist and prolonged contact with skin.
GENERAL USE PRECAUTIONS
- A maximum of 3 pt. of Prefix Herbicide (or a maximum of 0.375 lb. a.i./A of fomesafen from any product containing fomesafen: Flexstar, Prefix, or Reflex) may be applied per acre per year in Region 1 (see Regional Use Map).
- A maximum of 3 pt. of Prefix Herbicide (or a maximum of 0.375 lb. a.i./A of fomesafen from any product containing fomesafen: Flexstar, Prefix, or Reflex) may be applied per acre in ALTERNATE years in Region 2 (see Regional Use Map).
- A maximum of 2.5 pt. of Prefix Herbicide (or a maximum of 0.313 lb. a.i./A of fomesafen from any product containing fomesafen: Flexstar, Prefix, or Reflex) may be applied per acre in ALTERNATE years in Region 3 (see Regional Use Map).
- A maximum of 2 pt. of Prefix Herbicide (or a maximum of 0.25 lb. a.i./A of fomesafen from any product containing fomesafen: Flexstar, Prefix, or Reflex) may be applied per acre in ALTERNATE years in Region 4 (see Regional Use Map).
- Avoid overlapping spray swaths, as injury may occur to rotational crops.
- Do not graze treated areas or harvest for forage or hay.
- Do not exceed 2.48 lb. a.i./A/crop of S-metolachlor (0.571 gallon/A Prefix Herbicide).
- Do not exceed 2.48 lb a.i./A per year of S-metolachlor from applications of Prefix or any other metolachlor-containing product.
- To prevent off-site movement due to runoff or wind erosion:
- Avoid treating powdery dry or light sand soils when conditions are favorable for wind erosion.
Under these conditions, the soil surface should first be settled by rainfall or irrigation.
- Do not apply to impervious substrates, such as paved or highly compacted surfaces.
- Do not use tailwater from the first flood or furrow irrigation of treated fields to treat non-target crops, unless at least 1/2 inch of rainfall has occurred between application and the first irrigation.
(Maximum Rate 3 pt./A per year)
REGION 1 - Includes the following states or portion of states where Prefix Herbicide may be applied: Alabama, Arkansas, Georgia, Louisiana, Mississippi, Missouri (counties of Bollinger, Butler, Cape Giradeau, Dunklin, Madison, Mississippi, New Madrid, Pemiscot, Perry, Ripley, Scott, Stoddard and Wayne), North Carolina, Oklahoma (East of U.S. Highway 75 and East of Indian Nation Parkway), South Carolina, Tennessee, and Texas (includes area east of U. S. Highway 77 to State Road 239 including all of Calhoun County).
(Maximum Rate 3 pt./A, alternate years)
REGION 2 - Includes the following states or portion of states where Prefix Herbicide may be applied: Delaware, Kentucky, Maryland, Virginia, West Virginia, South of Interstate 70 in the following states: Illinois, Indiana and Ohio and all areas South of Interstate 80 to the intersection of U.S. Highway 15 and East of U.S. Highway 15 and U.S. Highway 522 in Pennsylvania.
(Maximum Rate 2.5 pt./A, alternate years)
REGION 3 - Includes the following states or portion of states where Prefix Herbicide may be applied: Connecticut, Iowa, Maine, Massachusetts, Missouri (all counties except for those listed in Region 1), New Hampshire, New Jersey, New York, Pennsylvania (all areas except those listed in Region 2), Rhode Island, Vermont and Wisconsin (South of U.S. Highway 18 between Prairie Du Chien and Madison, and South of Interstate 94 between Madison and Milwaukee), and North of Interstate 70 in following states: Indiana, Illinois and Ohio.
(Maximum Rate 2 pt./A, alternate years)
REGION 4 - Includes the following states or portion of states where Prefix Herbicide may be applied: Kansas (all counties east of or intersected by U.S. Highway 281), Michigan (Southern Peninsula), Minnesota (all areas South of Interstate 94), Nebraska (all counties east of or intersected by U.S. Highway 281), and Wisconsin (all areas, except those in Region 3, South of Interstate 94 from Minnesota state line to Eau Claire and South of U.S. Highway 29 from Eau Claire to Green Bay plus Door and Kewaunee counties. The following counties are excluded: Clark, Marathon, Wood, Portage, Adams, Shawano, Waupaca, Waushara and Marquette). North Dakota (all areas East of Interstate 29 from Fargo south to the South Dakota state line). South Dakota (all areas East of Interstate 29 from the North Dakota state line to Watertown, all areas east of Highway 81 from Watertown to Madison and all areas East and South of State Road 34 and U.S. Highway 281 to the Nebraska state line).
If replanting is necessary in fields previously treated with Prefix Herbicide, the field may be replanted to soybeans. During planting, a minimum of tillage is recommended. Do not apply a second application of Prefix Herbicide or any product that contains metolachlor, fomesafen, or S-metolachlor as crop injury or illegal residues may occur in harvested soybeans.
Where a rate range is within a soil texture/organic matter classification, use a lower rate on soils that are relatively coarse-textured and/or low in organic matter. Use a higher rate on soils that are relatively fine-textured and/or high in organic matter.
Prefix Herbicide, when applied as directed, will control or partially control the following weeds.
Refer in the label regarding tank mix information.
PREFIX HERBICIDE FOUNDATION TREATMENT FOR PLANNED TWO-PASS WEED CONTROL PROGRAMS IN ALL TILLAGE SYSTEMS
Prefix Herbicide at 2 pt./A may be applied as a preemergence application on all soils to reduce competition from weeds for a period of up to 5 weeks when followed by a planned postemergence herbicide application in conventional and glyphosate-tolerant soybeans. Refer to Table 2 for weeds controlled or partially controlled. For the postemergence herbicide application, consult the selected postemergence herbicide manufacturer’s label for weeds controlled, optimum weed size, application rate, additional use directions, precautions, and limitations before use.
Preemergence: Apply Prefix Herbicide at 2 pt./A during planting (behind the planter), or after planting, but before weeds or soybeans emerge in conventional, conservation, or no-till systems. If weeds are present at the time of treatment, apply Prefix Herbicide in a tank mixture with a burndown herbicide (such as, Gramoxone Inteon or glyphosate brands). Follow with a postemergence herbicide applied at the labeled rate and within the specific growth stage for soybeans and weed spectrum. Recommended postemergence treatments include any product or combination of products labeled to control the specific weeds remaining in the field, including glyphosate (such as, Touchdown or Roundup) brands (for use on glyphosate-tolerant soybeans only).