General Information


MIXING: When using TRIPZIN ZC herbicide, make sure the sprayer is completely clean, free of rust or corrosion which occurs from winter storage. Examine strainers and screens to be sure the sprayer is clean from previously used pesticides.

Keep any tank mix containing TRIPZIN ZC herbicide agitated and spray out immediately. Do not allow tank mixes to stand for prolonged periods of time. The proper mixing procedure for TRIPZIN ZC herbicide alone or in tank mix combinations with other herbicides is:

1. Fill the spray tank 1/4 to 1/3 full with clean water.

2. Add labeled rate of TRIPZIN ZC herbicide while recirculating and with agitator running.

3. Follow the triple rinse procedure described under STORAGE AND DISPOSAL to insure that all product is removed from the container.

4. Mix thoroughly and add clean water to fill spray tank to desired level.

5. Add the other herbicide to tank last and agitate thoroughly.

6. Continue agitation during application and until sprayer tank is empty.


TRIPZIN ZC herbicide may be applied in fluid fertilizer solutions to soybeans by following the appropriate mixing procedures and compatibility check. When using tank mix combinations, be sure all components are compatible. Sprayable fluid fertilizer should NOT be used as a carrier after crop emergence unless the typical fertilizer burn symptoms on the crop are acceptable.

Due to variability of fertilizers, make a compatibility check of TRIPZIN ZC herbicide and tank mix combinations which include TRIPZIN ZC herbicide for each batch of fluid fertilizers.

Compatibility Check:

1. Pre-mix 2 teaspoonfuls of TRIPZIN ZC herbicide with 8 teaspoonfuls of water (1:4 ratio) in a quart jar by adding the water first followed with TRIPZIN ZC herbicide. Mix thoroughly. If a second herbicide is to be used, double the amount of water (1:8 ratio) and add the second herbicide after mixing TRIPZIN ZC herbicide first.

2. Then pour 1 pint of fluid fertilizer into the quart jar and shake well.

3. Allow to stand for 5 minutes.


Interpretation of Results: If the solution in the jar appears to be uniform, without signs of agglomeration, or without a separation of an oily film on top of the fertilizer, the mixture may be used. If not, repeat the compatibility check using twice the amount of water or add a compatibility agent to the water. If separation occurs, but the mixture can be re-suspended by shaking, then application is possible with good agitation in the spray tank.

Tank Mixing Guidelines:

1. Add the required amount of water and compatibility agent (if required) to the tank. Start agitation system while adding TRIPZIN ZC herbicide and follow by adding the fluid fertilizer and agitate.

2. If a second herbicide is to be used, follow as above in 1, but use twice the amount of water. Start agitation and add TRIPZIN ZC herbicide and follow by adding the second herbicide, and then continue filling the tank with fluid fertilizer.

3. Maintain continuous agitation to assure uniform spray mixture until the tank is emptied.


Dry bulk fertilizer may be impregnated or coated with TRIPZIN ZC herbicide for application to alfalfa and soybeans. All recommendations, cautions, and special precautions on this label must be followed along with state regulations relating to dry bulk fertilizer blending, impregnating and labeling.

Impregnation: To impregnate, use a system consisting of a belt, conveyor, or closed drum which is used for dry bulk fertilizer blending. Any commonly used fertilizer can be impregnated with TRIPZIN ZC herbicide except ammonium nitrate, potassium nitrate, or sodium nitrate. Do not use on powdered limestone. Apply using a minimum of 200 lbs dry bulk fertilizer per acre and up to a maximum of 450 lbs per acre. To impregnate or coat dry bulk fertilizer, mix TRIPZIN ZC herbicide with sufficient water to form a sprayable slurry. The delivery nozzles must be directed to deliver a fine spray toward the fertilizer for thorough coverage while avoiding spray contact with mixing equipment. Uniform impregnation of TRIPZIN ZC herbicide to dry bulk fertilizer will vary and if the absorptivity is not adequate, an adsorptive powder may be added to produce a dry, free-flowing mixture. Micro-Cel E (Johns-Manville Product Corporation) is the recommended absorbent powder. When another herbicide is used with TRIPZIN ZC herbicide, mix and impregnate immediately. Apply immediately after impregnation unless experience has shown that impregnated fertilizer can be stored without becoming lumpy and difficult to spread.

Rates: Select the rate of TRIPZIN ZC herbicide per acre from the appropriate section of this label and refer to the formula below to determine the amount of TRIPZIN ZC herbicide which is to be impregnated on a ton of dry bulk fertilizer based on the amount of fertilizer which will be distributed on one acre.

APPLICATION: Uniform application is essential for satisfactory weed control. Accurate calibration of fertilizer application equipment is essential for uniform distribution to the soil surface. For best results apply 1/2 the specified rate and overlap 50 percent, or double apply by splitting the middles to obtain the best distribution pattern.

If fertilizer materials are excessively dusty, use diesel oil or other suitable additive to reduce dust prior to impregnation as dusty fertilizer will result in poor distribution during application. Crop injury and/or poor weed control may occur where the impregnated fertilizer is not uniformly applied.

INCORPORATION AND COMBINATION USES: It is the pesticide user’s responsibility to ensure that all products are registered for the intended use. Read and follow the applicable restrictions, limitations, and directions for use on all product labels involved in tank mixing. Users must follow the most restrictive directions for use and precautionary statements of each product in the tank mixture.

SOIL TEXTURE: As used on this label, “Coarse soils” are loamy sand or sandy loam soils. “Medium soils” are loam, silt loam, silt, sandy clay, or sandy clay loam. “Fine soils” are silty clay, silty clay loam, clay, or clay loam. Silty clay loam soils are transitional soils and may be classified as medium textured soils in some regions of the U.S.

Apply this product only as specified on this label.
Do not allow sprays to drift on to adjacent desirable plants.
Do not allow spray to drift from the application site and contact people, structures
people occupy at any time and the associated property, parks and recreation areas, nontarget crops, aquatic and wetland areas, woodlands, pastures, rangelands, or animals.

Observe the most restrictive cautions and limitations on labeling of all products used in mixtures.

For all uses: Low-pressure and high volume hand-wand equipment is prohibited.


Apply TRIPZIN ZC herbicide through sprinkler irrigation equipment to potatoes and soybeans as directed on this label. Refer to the crop sections of this label for rates, weeds controlled or suppressed, restrictions, and special precautions. Apply this product only through sprinkler (including center pivot, lateral move, or solid set) irrigation systems. 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 non-uniform distribution of treated water.

Calibration: (Center Pivot and Self-Propelled Lateral Move Systems):

Sprinkler irrigation systems must be accurately calibrated for application of TRIPZIN ZC herbicide. Greater accuracy in calibration (and distribution) will be achieved by injecting a larger volume of a more dilute mixture of product and water per hour. Follow the steps below to calibrate center pivot and lateral move systems:

1. Determine number of minutes required to make one complete revolution while applying 1/4 to 3/4 inch of water per acre.

2. With the system at operating pressure determine the exact number of minutes required to inject one gallon of water.

3. Divide the time required for one revolution (step 1) by the time required to inject one gallon (step 2). This gives total gallons of product-water mixture to be added to nurse tank.

4. Add required amount of water to nurse tank and start the agitation system. Then add sufficient TRIPZIN ZC herbicide at the labeled rate (See BROADCAST APPLICATIONS) to the nurse tank.

EXAMPLE: If 20 hours (1200 minutes) were required for one revolution and if 2 minutes were required to inject one gallon, then a total of 600 gallons of product-water mixture are required (1200 ÷ 2 = 600); to treat 135 acres at 1 pint/acre, 135 pints (16 gallons and 7 pints) of TRIPZIN ZC herbicide are required.

If you have questions about calibration, contact State Extension Service Specialists, equipment manufacturers or other experts.

Restrictions and Precautions for Chemigation:

- Do not connect any irrigation system (including greenhouse systems) used for pesticide application to a public water system unless the pesticide labelprescribed 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.

- The system must contain a functional check valve, vacuum relief valve, and low pressure drain appropriately located on the irrigation pipeline to prevent water source contamination from backflow.

- The pesticide injection pipeline must contain a functional, automatic, quickclosing check valve to prevent the flow of fluid back toward the injection pump.

- The pesticide injection pipeline must also contain a functional, normally closed, solenoid-operated valve located on the intake side of the injection pump and connected to the system interlock to prevent fluid from being withdrawn from the supply tank when the irrigation system is either automatically or manually shut down.

- The system must contain functional interlocking controls to automatically shut off the pesticide injection pump when the water pump motor stops.

- The irrigation line or water pump must include a functional pressure switch which will stop the water pump motor when the water pressure decreases to the point where pesticide distribution is adversely affected.

- Systems must use a metering pump, such as a positive displacement injection pump (e.g. diaphragm pump) effectively designed and constructed of materials that are compatible with pesticides and capable of being fitted with a system interlock.

- Do not apply when wind speed favors drift beyond the area intended for treatment.

- Maintain continuous agitation in the injection nurse tanks during the herbicide application, sufficient to keep herbicide in suspension.

- Apply specified dosage in 1/4 to 3/4 inch of water (1/4 to 1/2 inch of water on sandy soils) per acre as a continuous injection in center pivot and lateral move systems or in the last 15 to 30 minutes of set in permanent solid set sprinkler systems. Application of more than the quantity of irrigation water indicated on this label may result in decreased product performance by removing the chemical from the zone effectiveness. Where sprinkler distribution patterns do not overlap sufficiently, unacceptable weed control may result. Where sprinkler distribution patterns overlap excessively, crop injury may result. Allow sufficient time for pesticide to be flushed through all lines and all nozzles before turning off irrigation water. To insure that lines are flushed and free of remaining pesticide, an indicator dye may be injected into the lines to mark the end of the application period.

- Use a minimum of 1 part water to 1 part herbicide for injection. The use of a larger volume of water will insure greater accuracy and more uniform distribution.


Avoiding spray drift at the application site is the responsibility of the applicator. The interactions of many equipment-and-weather-related factors determine the potential for spray drift. The applicator and the grower are responsible for considering all these factors when making decisions.

The following drift management requirements must be followed to avoid offtarget drift movement from aerial applications to agricultural field crops. These requirements do not apply to forestry applications, public health uses or to applications using dry formulations.

1. The distance of the outer most nozzles on the boom must not exceed 3/4 the length of the wingspan or rotor.

2. Nozzles must always point backward parallel with the air stream and never be pointed downwards more than 45 degrees.

3. Where states have more stringent regulations, they must be observed.

4. The applicator must be familiar with and take into account the information covered in the Aerial Drift Reduction Advisory Information.

INFORMATION ON DROPLET SIZE: The most effective way to reduce drift potential is to apply large droplets. The best drift management strategy is to apply the largest droplets that provide sufficient coverage and control. Applying larger droplets reduces drift potential, but will not prevent drift if applications are made improperly, or under unfavorable environmental conditions (see WIND, TEMPERATURE AND HUMIDITY, and TEMPERATURE INVERSIONS).

SENSITIVE AREAS: Apply TRIPZIN ZC herbicide only when the potential for drift to adjacent sensitive areas (e.g. residential areas, bodies of water, known habitat for threatened or endangered species, non-target crops) is minimal (e.g. when wind is blowing away from the sensitive areas).


Use a standard low pressure (20 to 40 psi) herbicide boom sprayer equipped with suitable nozzles and screens no finer than 50-mesh in nozzle and in-line strainers. Agitate thoroughly before and during application with bypass agitation.

GROUND APPLICATION: Apply the specified rate of TRIPZIN ZC herbicide in a minimum of 10 to 40 gallons of spray mixture per acre broadcast.

AERIAL APPLICATION: Where permitted, apply specified rate in a minimum of 2 to 10 gallons of spray mixture per acre. Do not apply aerially when wind speed is greater than 10 mph.

For All Applications of TRIPZIN ZC herbicide: Sprayer must be accurately calibrated before applying TRIPZIN ZC herbicide. Check sprayer during application to be sure it is working properly and delivering a uniform spray pattern. As the volume of spray mixture decreases per acre, the importance of accurate calibration and uniform application increases. Avoid over application, misapplication, and boom and spray swath overlapping that will increase spray dosage. (Crop injury may occur as a result.) Avoid spray skips and gaps which allow weeds to grow in untreated soil. Do not apply when weather conditions favor spray drift and/or when sensitive or cool season crops, such as cole crops, onions, peas, or strawberries are present in adjacent fields or in areas where wheat is growing in coarse textured soils.

SPRAYER CLEANUP: Spray equipment must be thoroughly cleaned to remove remaining traces of herbicide that might injure other crops to be sprayed. Drain any remaining spray solution of TRIPZIN ZC herbicide from the spray tank and dispose of according to label disposal instructions. Rinse the spray tank and refill with water, adding a heavy-duty detergent at the rate of one cup per 20 gallons of water. Recycle this mixture through the equipment for 5 minutes and spray out. Repeat this procedure twice. Fill the spray tank with clean water, recycle for 5 minutes, and spray out. Clean pump and nozzle screens thoroughly. Wash away any spray mixture from the outside of spray tank, nozzles or spray rig. All rinse water must be disposed of in compliance with local, state, and Federal guidelines.

Certain varieties are more sensitive than others to pendimethalin and/or metribuzin, the active ingredients in TRIPZIN ZC herbicide. Consult with your seed supplier or refer to State Extension recommendations for information on the tolerance to pendimethalin and/or metribuzin products of labeled crop varieties.

Limitations, Restrictions, and Exceptions


Application Methods: Apply by ground, air, or chemigation.

Use Methods, Timings, and Use Rates
Apply TRIPZIN ZC herbicide preemergence or early postemergence in potatoes.

Preemergence. Apply after planting, but before potatoes and weeds emerge, or after dragoff.

Early Postemergence (ONLY Russet or white skinned varieties that are not early maturing). Apply from crop emergence to the 6-inch stage of growth.

Chemigation Applications. Apply TRIPZIN ZC herbicide through sprinkler irrigation systems. Apply preemergence after planting, after dragoff, or early postemergence through sprinkler irrigation systems. Follow all directions, special instructions and precautions about chemigation in the CHEMIGATION section of this label.

- Application of TRIPZIN ZC herbicide on White Rose variety potatoes during or followed by cool and/or wet weather conditions may result in crop injury.

- DO NOT apply to sweet potatoes or yams.
- DO NOT apply preplant.
- DO NOT make more than one application per season.
- DO NOT apply postemergence if potatoes are under stress from cold/wet or hot/dry conditions or crop injury may occur.
- ONLY make postemergent applications to Russet and white skinned varieties that are not early maturing.
- DO NOT rotate any crop not listed on this label for 18 months following application to potatoes.
- Preharvest Interval (PHI): DO NOT apply within 60 days of harvest.
- DO NOT use air blast sprayers.
- DO NOT make postemergent applications prior to rainfall or irrigation on recently cultivated potatoes.

Pre-Harvest Interval

60 days

Restricted Entry Interval

24 hours
Exception: If the product is soil-injected or soil-incorporated, the Worker Protection Standard, under certain circumstances, allows workers to enter the treated area if there will be no contact with anything that has been treated.