General Information


Read all label directions before using.

SINISTER is a selective herbicide which may be applied pre plant surface, preemergence and/or postemergence for control or partial control of broad leaf weeds, grasses and sedges in cotton, dry beans, potatoes, snap beans and soybeans.

Preplant Surface and Preemergence Applications

Certain germinating broad leaf weeds, grasses and sedges can be controlled or partially controlled by soil residual activity from either preplant surface or preemergence applications of SINISTER. Moisture is necessary to activate SINISTER in soil for residual weed control. Dry weather following applications of SINISTER may reduce effectiveness. When adequate moisture is not received after a SINISTER application, weed control may be improved by overhead irrigation with at least a % inch of water.

Postemergence Applications

SINISTER is generally most effective when used postemergence, working through contact action.

Therefore, emerged weeds must have thorough spray coverage for effective control. Best broad-spectrum postemergence control of susceptible broadleaf weeds is obtained when SINISTER is applied early to actively growing weeds. This usually occurs within 14 to 28 days after planting. Refer to the weed control tables for specific recommendations on weed growth stages and rates. Some bronzing, crinkling or spotting at labeled crop leaves may occur following postemergence applications, but labeled crops soon outgrow these effects and develop normally.

Soil Characteristics

Application of SINISTER to soils with high organic matter and/or high clay content may require higher rates than soils with low organic matter and/or low clay content. Refer to the SINISTER Regional Use Map, weed control tables, and specific crop use sections for recommendations on use rates based on soil texture.

Environmental and Agronomic Conditions

Always apply SINISTER under favorable environmental conditions that promote active weed growth.

Avoid applying SINISTER to weeds or labeled crops which are under stress from drought, extreme temperatures, excessive water, low humidity, low soil fertility, mechanical or chemical injury as reduced weed control and/or increased crop injury may result.


SINISTER requires a 1 hour rain-free period for best results when applied postemergence.


Cultivation prior to postemergence application is not recommended. Cultivation may put weeds under stress, reducing weed control. Timely cultivation 1-3 weeks after applying SINISTER may assist weed control.

Information on Weed Resistance

Naturally occurring biotypes of certain broadleaf species with resistance to this herbicide and related products (same mode of action) are known to exist. Selection of resistant biotypes, through repeated use of these herbicides, may result in control failures.

If poor performance cannot be attributed to adverse weather conditions or improper application methods, a resistant biotype may be present. In such a case, additional treatments with this herbicide or similar mode of action products are not recommended. Consult your local company representative or agricultural advisor for assistance.


Drift Management

Avoiding spray drift at the application site is the responsibility of the applicator and the grower. The interaction of many equipment and weather-related factors determines the potential for spray drift. The applicator and grower must consider the interaction of equipment and weather-related factors to ensure that the potential for drift to sensitive nontarget plants is minimal.

This pesticide may only be applied when the potential for drift to adjacent sensitive areas (e.g., residential areas, bodies of water, nontarget plants) is minimal (i.e., when the wind is blowing away from the sensitive area).

Spray Additives

Only spray additives cleared for use on growing crops under 40 CFR 180.1001 may be used in spray mixture.

For Postemergence Applications One of The Following May Be Added Except in Tank Mix With Products Prohibiting Spray Additives:

Nonionic Surfactant (NIS) – Use NIS containing at least 75% surface active agent at 0.25 to 0.5% v/v (1-2 qts./100 gals.) of the finished spray volume.

Crop Oil Concentrate (COC) – Use a nonphytotoxic COC containing 15-20% approved emulsifier, at 0.5-1% v/v (0.5-1 gal./100 gals.) of the finished spray volume. COC can improve weed control but may slightly reduce crop tolerance.


Preplant Surface and Preemergence Application – Use a minimum of 10 gallons per acre. Nozzle selection should meet manufacturer's gallonage and pressure recommendations for preplant surface or preemergence applications.

Postemergence Application – Use sufficient spray volume and pressure to ensure complete coverage of the target weed. A spray volume of 10-20 gallons per acre and 30-60 psi at the nozzle tip is recommended. On large weeds and/or dense foliage. Use 60 psi and a minimum of 20 gallons per acre to ensure coverage of weed foliage.

The use of flat fan nozzles will result in the most effective postemergence application of SINISTER. Use nozzles that are set up to deliver medium quality spray (ASAE Standard S-572).



Calculate the amount of herbicide and water volume needed for band treatment by the formula given in the label.

NOTE: Thorough weed coverage is important for postemergence band applications. Best coverage is obtained with a minimum of two nozzles, one directed to each side of the planted row. Application with a single nozzle directed over the top of the row is not recommended for postemergence applications but is suitable for preemergence applications. Cultivation of untreated areas may be needed following band applications. When making post emergence band applications and cultivating in the same operation, intercept spray, reducing weed coverage resulting in less than adequate weed control.


Use sufficient spray volume and pressure to ensure complete coverage of the target. A minimum of 5 gallons per acre of spray mixture should be applied with a maximum of 40 PSI pressure. When foliage is dense, use a minimum of 10 gallons per acre to ensure coverage of weed foliage.



SINISTER alone or in tank mixture with other herbicides on this label, which are registered for center pivot application, may be applied in irrigation water preemergence (after planting but before weeds or crop emerge) at rates recommended on this label. SINISTER also may be applied postemergence to the crop and preemergence to weeds in crops where postemergence applications are allowed on this label. Follow all restrictions (height, timing, rate, etc.) to avoid illegal residues. Apply this product only through a center pivot irrigation system. Do not apply this product through any other type of irrigation system. Crop injury, lack of effectiveness, or illegal pesticide residues in the crop can result from nonuniform distribution of treated water. If you have questions about calibration, you should contact State Extension specialists, equipment manufacturers, or other experts. Do not connect an irrigation system (including greenhouse systems) used for pesticide application to a public water system, unless the pesticide label-prescribed safety devices for public water systems are in place. A person knowledgeable of the chemigation system and responsible for its operation, or under the supervision of the responsible person, shall shut the system down and make necessary adjustments should the need arise.


- Thoroughly clean the spray system with water and a commercial tank cleaner before and after each use.

- Tank mixes of SINISTER with other pesticides, fertilizers or any other additives except as specified on this label or other approved Syngenta supplemental labels may result in tank-mix incompatibility, unsatisfactory performance or unsatisfactory crop injury.

- Avoid overlapping spray swaths, as injury may occur to rotational crops.

- To provide adequate coverage, it is recommended that ground speed not exceed 10 mph during application.

- Avoid drift to all other crops and nontarget areas. Crops other than those labeled may be severely injured by drift. Do not apply when wind velocity exceeds 15 mph.


- A maximum of 1.05 pts. of SINISTER (or a maximum of 0.375 lb. a.i./A of fomesafen from any product containing fomesafen) may be applied per acre per year in Region 1 (see Regional Use Map).

- A maximum of 1.05 pts. of SINISTER (or a maximum of 0.375 lb. a.i./A of fomesafen from any product containing fomesafen) may be applied per acre in ALTERNATE years in Region 2 (see Regional Use Map).

- A maximum of 0.87 pt. of SINISTER (or a maximum of 0.313 lb. a.i./A of fomesafen from any product containing fomesafen) may be applied per acre in ALTERNATE years in Region 3 (see Regional Use Map).

- A maximum of 0.70 pt. of SINISTER (or a maximum of 0.25 lb. a.i./A of fomesafen from any product containing fomesafen) may be applied per acre in ALTERNATE years in Region 4 (see Regional Use Map).

- A maximum of 0.52 pt. of SINISTER (or a maximum of 0.1875 lb. a.i./A of fomesafen from any product containing fomesafen) may be applied per acre in ALTERNATE years in Region 5 (see Regional Use Map).

- Do not make ground or aerial application during temperature inversions.


If replanting is necessary in fields previously treated with SINISTER, the field may be replanted to cotton, dry beans, potatoes, snap beans or soybeans. During replanting, a minimum of tillage is recommended to preserve the herbicide barrier for effective weed control. Do not apply a second application of SINISTER or other fomesafen containing product as crop injury or illegal residues may occur in harvested crops. If tank-mix combinations were used, refer to product labels for any additional replanting instructions.

Limitations, Restrictions, and Exceptions


Preemergence Application

Apply SINISTER preemergence at 0.70 - 1.05 pints per acre in cotton for control or partial control of the weeds listed in Table 1. Apply as a preemergence treatment only to coarse textured soils (sandy loam, loamy sand, sandy clay loam). Do not apply as a preemergence treatment to medium or fine-textured soils as crop injury will likely occur. To broaden the weed control spectrum, SINISTER may be tank mixed with other preemergence herbicides such as Caparol. Cotoran, Direx, Karmex, Solicam, or Staple. For control of emerged weeds, SINISTER may be tank mixed with a burndown herbicide such as Gramoxone Inteon or glyphosate brands (such as Touchdown, Showdown, or Roundup) labeled in cotton. In reduced tillage plantings, SINISTER can be applied up to 14 days prior to planting or at planting with a burndown herbicide. Refer to the tank-mix partner label for use directions, restrictions and limitations. The most restrictive product labeling applies.

Cotton plants are tolerant to preemergence applications of SINISTER when applied at recommended rates and to coarse textured soil types. Some crinkling or spotting of cotton foliage or stunting may occur, especially if heavy rainfall occurs during or soon after cotton emergence, but cotton plants normally outgrow these effects and develop normally.

Cotton foliage is not tolerant to SINISTER. Do not apply SINISTER over the top of emerged cotton as unacceptable cotton injury will occur.

Product Use Restrictions - Cotton
Do not apply SINISTER later than 70 days before harvest.
Do not apply more than 1.05 pints per acre of SINISTER in any year.

Pre-Harvest Interval

70 days

Restricted Entry Interval

24 hours