RICE- DELAYED PREEMERGENCE - LOAM, SILT LOAM, ETC.

General Information

Product Information

Prowl H2O herbicide is a selective herbicide for controlling most annual grasses and certain broadleaf weeds as they germinate. Refer to Table 1 for crop uses. Refer to Table 2 for a complete list of controlled weeds. Prowl H2O will not control established weeds.

Mode of Action

Prowl H2O herbicide is a meristematic inhibitor that interferes with the plant’s cellular division or mitosis. This and/or other products with the meristematic-inhibiting mode of action may not effectively control naturally occurring biotypes of some of the weeds listed on this label. A weed biotype is a naturally occurring plant within a given species that has a slightly different, but distinct, genetic makeup from other plants. Other herbicides with the meristematic-inhibiting mode of action include other dinitroaniline herbicides, such as trifluralin. If naturally occurring meristematic-inhibiting resistant biotypes are present in a field, Prowl H2O and/or any other meristematic inhibiting mode of action herbicide should be tank mixed or applied sequentially with an appropriate registered herbicide having a different mode of action to ensure control.

Application Rate
Use rates for Prowl H2O when used alone, in tank mix, or for sequential applications are given in Crop-specific Information. Use rates of this product vary by soil texture and organic matter. See Table 3 for soil texture groupings used in this label.

DO NOT apply more than the maximum labeled rate of Prowl H2O for any soil type.

Application Timings

Prowl H2O will provide most effective weed control when applied by ground or aerial equipment and subsequently incorporated into soil by rainfall, sprinkler irrigation, or mechanical tillage before weed seedling germination. Prowl H2O can also be applied through chemigation, including flooded basin irrigation systems. Prowl H2O may be applied preplant surface, preplant incorporated, surface incorporated, preemergence, early postemergence, postemergence incorporated (CULTI-SPRAY), or by layby treatment. See Crop-specific Information for specific application directions and restrictions by crop.

Preplant Surface Application. For use in minimum-tillage or no-tillage production systems, apply Prowl H2O alone or in tank mixes within 45 days of planting. When making early preplant surface application (15 to 45 days before planting), Prowl H2O should be tank mixed or followed by a postemergence herbicide application. Rainfall or sprinkler irrigation after application is required to move this product into the upper soil surface where weed seeds germinate.

Preplant Incorporated Application. Apply Prowl H2O and incorporate into the upper (1 inch to 2 inches) soil surface within 60 days of planting. Use an implement capable of giving uniform incorporation; two-pass incorporation usually results in a more consistent result.

Surface Incorporated Application. Uniformly apply Prowl H2O as broadcast or banded treatment to soil surface underneath established trees and/or in ground areas between trees rows. Incorporate into upper (1 inch to 2 inches) soil surface using rainfall, sprinkler irrigation, or shallow mechanical incorporation using an implement capable of giving uniform incorporation; two-pass mechanical incorporation usually results in a more consistent result.
Preemergence Surface Application. Broadcast treatment uniformly to the soil surface at planting and up to 2 days after planting (refer to Crop-specific Information section for exceptions). Rainfall, sprinkler irrigation, or shallow mechanical incorporation after application is required to move this product into the upper soil surface where weed seeds germinate. If adequate rainfall or irrigation does not occur, or soil crusting or soil compaction has occurred, and weed seedling emergence begins, a shallow cultivation or rotary hoeing or light harrow will improve performance. Make sure that crop seeds are below the tilled soil surface area.

Early Postemergence Application. Prowl H2O must be applied before weed seedling emergence or in a tank mix with products that control the emerged weeds. Refer to Crop-specific Information for specific postemergence application instructions by crop.

Postemergence Incorporated Application (CULTISPRAY). Before application, crop must be cultivated in such a manner as to throw at least 1 inch of soil over the base of the crop plants. This will prevent direct contact of Prowl H2O and the zone of brace root formation.
Prowl H2O must be applied broadcast with a ground sprayer when crop is at least 4 inches tall up to layby. Use drop nozzles if crop foliage will prevent uniform coverage of the soil surface within the rows. Thoroughly and uniformly incorporate Prowl H2O treatments into the soil:

1. With a sweep-type or rolling cultivator set to provide thorough incorporation in the top 1 inch of soil, or 2. With adequate overhead irrigation water or rainfall. See Crop-specific Information (Corn and Grain Sorghum) for more details on (CULTI-SPRAY) application.

Layby Application. Apply Prowl H2O directly to the soil between rows as a directed spray after the last normal cultivation (layby). See Crop-specific Information for more details on layby application.

Split Application. Prowl H2O may be applied preplant incorporated within 60 days of planting and followed by a preemergence application at planting or up to 2 days after planting (refer to Crop-specific Information section for exceptions). The total amount of Prowl H2O herbicide applied per acre per season cannot exceed the highest labeled rate for any given soil type. See Crop-specific Information for more details on split applications.

Fall Application. Prowl H2O may be used in fall application programs in certain crops. See Crop-specific Information for details on fall application timing.

Spraying Instructions

Prowl H2O may be applied using water or sprayable fluid fertilizer (such as straight 32-0-0 or 28-0-0) as the spray carrier. Additionally, Prowl H2O may be impregnated on dry bulk fertilizer. Sprayable fluid fertilizer as a carrier is NOT for use after crop emergence unless the typical fertilizer burn symptoms on the crop are acceptable.

Aerial Application

Uniformly apply in 5 or more gallons of water per acre. Exercise caution to minimize drift. DO NOT apply during periods of gusty winds or when wind conditions favor drifting. Spray drift can cause injury to sensitive crops. Use a flagman or an automatic mechanical flagging unit on the aircraft to avoid overlapping and possible crop injury.

Ground Application (Broadcast)
Uniformly apply with calibrated ground equipment in 10 or more gallons of water per acre or 20 or more gallons of liquid fertilizer per acre. Use sprayers equipped with appropriate nozzles that provide uniform and accurate spray distribution and minimize drift. Keep the bypass line on or near the bottom of the tank to minimize foaming.

Nozzle and in-line screens must be no finer than 50 mesh.
Application of Prowl H2O during periods of gusty winds may result in uneven applications. DO NOT apply Prowl H2O postemergence in liquid fertilizers.
If liquid fertilizer/herbicide(s) mixture separates in the spray tank, clogged equipment and uneven application can result. Always predetermine the compatibility of Prowl H2O alone or with other herbicides based on the following compatibility jar test:
1. Add 1 pint of fertilizer to a quart jar.
2. Add 1 to 4 teaspoon(s) of the dry flowable (DF), wettable powder (WP), aqueous solution (AS), flowable (F), or liquid (L) formulation (depending on mixing ratio required) to the liquid fertilizer. To calculate teaspoons of the formulation to add:
3. Close the jar and agitate until the herbicide(s) are evenly dispersed in the liquid fertilizer. If the materials do not disperse well, it may be necessary to slurry the chemicals in water before adding to the fertilizer.
4. After dispersing the materials, add appropriate number of teaspoons of Prowl H2O to the jar and shake well. Add water soluble concentrate herbicides to the mixture last and agitate. Let the mixture stand for 30 minutes; then observe the results. Look for signs of separation: an oily layer or globules, sludge, flakes or other precipitates.
5. Evaluate compatibility.
a. If the herbicide(s) and liquid fertilizer mixture does not separate, use this mixture in your spray tank.
b. If the mixture separates but mixes readily with shaking, the mixture can be used if good agitation is maintained in the spray tank.
c. If separation of the mixture occurs and agitation does not correct this problem, a compatibility agent is needed.
6. If the need for a compatibility agent is demonstrated, BASF recommends the following procedure: Using a clean quart jar, repeat step 1 above and add 1/2 teaspoon of the compatibility agent to the liquid fertilizer. Mix well and repeat steps 2, 3, and 4. If separation or precipitation occurs with the compatibility agent, DO NOT use Prowl H2O with that specific liquid fertilizer.

Ground Application (Band)
Uniformly apply the broadcast equivalent rate and volume per acre.

Ground Application (Dry Bulk Fertilizer)
Apply Prowl H2O/dry bulk fertilizer mixtures only with ground equipment. See Crop-specific Information for crops suitable for dry bulk fertilizer applications. DO NOT impregnate Prowl H2O onto coated ammonium nitrate or limestone because these materials will not absorb the herbicide.
Dry fertilizer blends containing mixtures of ammonium nitrate or limestone may be impregnated with Prowl H2O. A minimum of 200 pounds of impregnated dry bulk fertilizer, excluding the weight of ammonium nitrate or limestone, must be applied per acre.

To impregnate Prowl H2O on bulk fertilizer, use a closed rotary-drum mixer or other commonly used dry bulk fertilizer blender equipped with suitable spray equipment. Spray nozzles must be placed to provide uniform coverage of Prowl H2O onto the fertilizer during mixing.

Apply the Prowl H2O herbicide/dry bulk fertilizer mixture with a calibrated dry fertilizer spreader. The Prowl H2O/dry bulk fertilizer mixture must be spread uniformly on the soil surface.

Chemigation Application via Sprinkler Irrigation and Drip Irrigation Systems

Prowl H2O may be applied as a chemigation treatment through sprinkler irrigation and drip irrigation systems.
Refer to Crop-specific Information sections for individual crops. DO NOT apply Prowl H2O via chemigation to crops unless specified in Crop-specific Information section.
Apply this product ONLY through a sprinkler irrigation system of the following type: center pivot, lateral move, end tow, side (wheel) roll, traveler, big gun, solid set, or hand move.
Apply this product ONLY through a drip irrigation system that has emitters above the soil surface.
DO NOT apply this product through any other type of sprinkler irrigation or drip irrigation system.
Uniform distribution of Prowl H2O-treated irrigation water is the sole responsibility of the applicator and is required to avoid crop injury, lack of herbicide effectiveness, or illegal pesticide residues in the crop. If you have any questions about calibration, contact State Extension Service specialists, equipment manufacturers, or other experts.
The system must be calibrated (with water only) to ensure the amount of Prowl H2O applied corresponds to the specified rate. Apply Prowl H2O in 1/2 to 3/4 inch of water during the first sprinkler set (use at least 1 inch of water in the states of New Mexico, Oklahoma, and Texas). BASF recommends mixing Prowl H2O with water at a 1:1 ratio in the injection nurse tank to assist with product flowability. Maintain agitation in the injection nurse tank to keep a uniform herbicide suspension during application. When application is complete, flush the system with water.

Application via Flood, Flooded Basin, or Gravity Flow Irrigation Systems

Prowl H2O herbicide may be applied via flood, flooded basin, or gravity flow irrigation systems, but only to the following crops: alfalfa, bearing and nonbearing fruit and nut trees, bearing and nonbearing olive trees, bearing and nonbearing vineyards, nonbearing date palm, and nonbearing fig trees.

Use Instructions and Restrictions for Flood, Flooded Basin, and Gravity Flow Irrigation

1. Prowl H2O may be applied through flood, flooded basin, or gravity flow irrigation systems designed to uniformly distribute irrigation water along the soil surface. Solid set systems using tall riser for overhead application are excluded.
2. Follow all label directions for Prowl H2O regarding rates per acre, timing of application, and crop-specific restrictions and precautions.
3. DO NOT connect an irrigation system used for pesticide application to a public water system unless the pesticide label prescribed safety devices for public water systems are in place.
4. 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.
5. BASF recommends that Prowl H2O is mixed with water at a 1:1 ratio in the injection nurse tank to assist with product flowability. Maintain agitation in the injection nurse tank to keep a uniform herbicide suspension during application. When application is complete, flush the system with water.
6. Systems using a gravity-flow pesticide dispensing system must meter the pesticide in the water at the head of the field downstream of a hydraulic discontinuity, such as a drop structure or weir box, to decrease potential for water source contamination from backflow water.
7. Tail water (runoff water) from flood, flooded basin, or gravity flow irrigation that contains Prowl H2O must be recirculated and/or contained in the field in a cistern or holding reservoir from the initial application and/or used only on adjacent approved crops for which Prowl H2O is registered for this type of application.
8. Systems using a pressurized water and pesticide injection system must meet the following requirements:
- The system must contain a functional check valve, vacuum relief valve, and low-pressure drain appropriately located in the irrigation pipe to prevent water source contamination from backflow.
- The pesticide injection pipeline must contain a functional, automatic, quick-closing check valve to prevent flow of fluids 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 automatically or manually shut down.
- The system must contain a functional interlocking control to automatically shut off the pesticide injection pump when the water pump stops.
- The irrigation pipe or water pump must include a functional pressure switch, which will stop the 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) of effective design and constructed of materials that are compatible with pesticides and capable of being fitted with a system interlock.
- Any alternative to the above safety devices must conform to the list of EPA-approved alternative devices.
9. Regularly measure the flow in the field to ensure the correct amount of Prowl H2O herbicide is metered into irrigation water and also regularly monitor to ensure treated water is uniformly distributed across the field.
Flow rates through metering devices and distribution of Prowl H2O can vary with water temperature and speed of water flow across the field.
10. Uniform distribution of Prowl H2O-treated irrigation water is the sole responsibility of the applicator and is required to avoid crop injury, lack of herbicide effectiveness, or illegal pesticide residues in the crop.
11. For questions about calibration, contact State Extension Service specialists, equipment manufacturers or other experts.

Use Precautions
- Prowl H2O herbicide will not control established weeds. Destroy emerged weeds before application.
- Prowl H2O is most effective in controlling weeds mechanically incorporated or when incorporated into the weed germination zone by adequate rainfall or overhead irrigation after application.
- In the event of a crop loss because of adverse weather conditions or other reasons, any crop registered for a preplant incorporated application of Prowl H2O can be replanted without adverse effects the same year (see Crop-specific Information for exceptions). If replanting is necessary, DO NOT work the soil deeper than the treated zone.
- Refer to Crop-specific Information for crop-specific preharvest intervals and feeding and grazing restrictions.

Crop-specific Information

Crop Injury. Prowl H2O herbicide use may result in crop injury, loss or damage to certain crops under a number of conditions, including but not limited to agronomic, cultural, mechanical, and environmental. Numerous risks of loss or damage to certain crops may be associated with the use of Prowl H2O even when directions for use are followed completely. The user or grower should take all such risks into consideration before deciding to apply the product.
BASF recommends testing on a small portion of the target crop to determine if damage is likely to occur. Each grower who is considering the product for such use should test Prowl H2O to determine its suitability.
A grower should use Prowl H2O only to the extent that, in his sole opinion, the benefit of Prowl H2O use outweighs the potential injury to the grower’s crop.
In addition, many factors can affect crop growth and/or yield, including but not limited to insects, diseases, weed competition, poor seed quality, improper planting depth, mechanical cultivation, poor weather (such as freezing or excessive wind, rain, heat, or cold), lack of or excessive moisture, crusting, fertility, or hardpans. Risk of loss or damage to crops may be associated with the use of Prowl H2O and contribute to poor stands because of failure of crop to emerge, swelling of roots or other belowground plant parts, less vigorous plant growth and development, and reduction in yield potential. Prowl H2O may also cause injury to sensitive rotational crops.

Limitations, Restrictions, and Exceptions

Rice

Prowl H2O may be applied by ground, air, or on dry bulk fertilizer (delayed preemergence and early postemergence applications only) to rice grown under conventional-tillage, reduced-tillage, minimum-tillage, or no-till systems, or on stale seedbeds.

Additional Weeds Controlled. In addition to weeds listed in Table 2, Prowl H2O controls the following weeds in rice: junglerice and sprangletop.

Use Method, Rate, and Timing

Delayed Preemergence. Apply Prowl H2O alone or with tank mix partner for delayed preemergence weed control in grain-drilled, dry-seeded rice. Apply Prowl H2O alone or in tank mix to levees after the levees are pulled and planted.
The seedbed should be firm and free of clods and must be prepared to allow for good seed coverage. Use of a planter under conditions that do not allow good soil coverage of the rice seed can result in reduced stand or stunting if Prowl H2O contacts germinating rice seed. Exposed seeds that come in contact with Prowl H2O may be injured. Apply only when growing conditions favor vigorous rice growth. The seedbed should have adequate moisture for seed germination. Not for use in grain-drilled, dryseeded rice in California.

Uniformly apply the specified rate of Prowl H2O after rice planting and before rice emergence (spiking) and weed germination. Apply after rice seed has absorbed water and germinated and after the soil has been previously sealed over the seed by at least 1 inch of rainfall or by irrigation (flush). If the soil has not been sealed by rain or flush, apply when 80 percent of germinated seeds have a primary root (radicle) or shoot at least 1/2-inch long. If there is insufficient moisture, BASF recommends flushing before Prowl H2O application to supply moisture for root (radicle) initiation and for vigorous rice and weed growth.

If applied to soil before these conditions, or to cracked soil, stand reduction or stunting of rice may occur. Under some conditions, use of gibberellic acid-treated seed, heavy rainfall after application, or flushing after application may result in herbicide injury to rice. Rice can overcome moderate injury with appropriate cultural practices.

Because of the residual activity of Prowl H2O, this treatment may be applied if rice is too small to maintain a flood on the field for weed control. However, proper water management practices must be followed for normal rice growth and activity of Prowl H2O.

Crop-specific Restrictions
- DO NOT apply Prowl H2O through any type of irrigation system.
- DO NOT apply in liquid fertilizer.
- DO NOT apply to rice fields if fields are used for fish production, especially catfish farming.
- Prowl H2O may be applied to rice fields used for crayfish production.
- DO NOT use water containing Prowl H2O residue from rice cultivation to irrigate food or feed crops not registered for use with Prowl H2O.
- In case of crop failure because of weather conditions or disease after treatment with Prowl H2O alone or in tank mix, only drilled dry-seeded rice may be immediately replanted; however, the grower assumes all risks and consequences associated with replanting of rice because there is the potential for stand reduction or stunting.
BASF recommends a 10% increase in seeding rate. Replant seed below the herbicide layer because reduced stand or stunting may occur if Prowl H2O contacts germinating rice seed. DO NOT replant with gibberellic acid-treated seed. DO NOT reapply Prowl H2O alone or in tank mix.
- DO NOT apply Prowl H2O and then flush for germination.
- DO NOT apply to stressed rice. Stress factors include cold or hot temperature extremes, excessive moisture or drought, problem soils, poor field drainage, or deep water after application.
- DO NOT apply early preemergence or preplant incorporated because severe rice injury is possible.

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.