General Information


This product is not recommended for use by homeowners.

Note: In the state of New York, this product may be applied only by commercial applicators.

For control of crabgrass and other annual grasses and broadleaf weeds,

use Quali-Pro Dithiopyr 40 WSB specialty herbicide in the following sites:

- established lawns

- commercial sod farms

- non cropland and industrial sites

- ornamental turf (including golf course fairways, roughs, tee boxes)

- landscape ornamentals, field grown and container nursery ornamentals. Quali-Pro Dithiopyr 40 WSB only controls crabgrass up to initiation of tillering, that is, when seedlings are first visible in established turfgrasses. Quali- Pro Dithiopyr 40 WSB will not control emerged weeds. For optimum effectiveness, apply Quali-Pro Dithiopyr 40 WSB prior to initiation of tillering, and make all other applications before germination of target weeds.

Quali-Pro Dithiopyr 40 WSB must be activated to be effective. Activation is achieved by watering-in from rainfall or irrigation (1/2 inch or more). Time applications to ensure that activation occurs before the tillering stage of crabgrass development or prior to germination of all other weeds.

Limitations, Restrictions, and Exceptions

Weed Control In Turf Grasses

Use Precautions for Turf Use and Turfgrass Safety

Before making the first application of Quali-Pro Dithiopyr 40 WSB, ensure that turfgrasses have developed a good root system and a uniform stand, and have been mowed at least two times following seeding, sodding or sprigging. Turf injury may result if Quali-Pro Dithiopyr 40 WSB is applied to turf that is not well-established, or has been weakened by weather-, pest-, disease-, chemical-, mechanical or other factors which lead to turf stress.

Quali-Pro Dithiopyr 40 WSB should only be applied as directed to established turfgrass species that have been determined to be tolerant to applications of this product. The following tables list tolerant turfgrass species.

Reseeding, Overseeding, or Sprigging

To ensure establishment of desirable turfgrasses, wait 10 weeks after a single application of Quali-Pro Dithiopyr 40 WSB, or 4 months after a split application program totaling more than 0.46 oz/1,000 sq ft (1.25 lb/acre) before reseeding, overseeding, or sprigging of treated areas. EXCEPTIONS: In cases where slight injury to perennial ryegrass can be tolerated, overseeding of bermudagrass with perennial ryegrass may be carried out as early as 6 weeks after application. To prevent injury to perennial ryegrass, overseed Bermudagrass 8 weeks after the Quali-Pro Dithiopyr 40 WSB application.

Follow normal cultural practices when reseeding or overseeding (soil cultivation, irrigation and fertilization). Best results are achieved using mechanical or power seeding equipment (slit seeders) which give good seed to soil contact.

Sod Production

- For best results, establish sod for at least six (6) months before a Quali- Pro Dithiopyr 40 WSB application is made.

- Do not apply this product within three (3) months of harvest.

Other Use Precautions

Crabgrass is controlled by early postemergence applications of Quali-Pro Dithiopyr 40 WSB only if applied prior to the fifth leaf (first tiller) stage of growth of crabgrass.

Perform activities that disturb the soil (such as core-, spike-, or hydro-aerification, and verticutting) before application of this product.

- Do not apply this product until the grass has recovered from these cultural practices.

- Do not use clippings from treated turf for mulching around vegetables or fruit trees.

- Do not graze livestock or feed foliage cut from areas treated with this product.

Application Directions

Application Equipment and Instructions: Quali-Pro Dithiopyr 40 WSB can be applied using conventional liquid application equipment. Use a sufficient volume of carrier solution to ensure a thorough and uniform spray application. Use of hand held spray guns are permitted.

Because of the variability in application use rates and spray patterns do not apply Quali-Pro Dithiopyr 40 WSB using liquid application equipment with cluster spray nozzles or other boomless spray equipment.

Calibrate application equipment prior to usage. Avoid streaking, skips, or excess overlaps during application. Use marker dyes or foams to assist in making more accurate applications.

Maximum Use Rates (All Turf Uses)

- Do not apply more than 0.5 lb ai/ acre per application or more than 1.5 lb ai/acre per year using split or sequential applications. These maximum use rates are equivalent to 4 water-soluble pouches per acre or 0.46 oz/1,000 sq ft (1.25 lb/acre of product) per application, and 12 water-soluble pouches per acre or 1.38 oz/1,000 sq ft (3.75 lb/acre of product) per year, respectively.

- In New York State, do not apply more than 0.25 lb ai per year. This is equivalent to 2 water-soluble pouches (0.625 lb/acre) per acre or 0.23 oz/1,000 sq ft of Quali-Pro Dithiopyr 40 WSB.

Fall Applications

For late summer or early fall (late August through November) applications, follow the “Program 3” use rates listed in the table “Programs for Crabgrass Control” for control of crabgrass through the early part of the next spring. Do not exceed maximum use rates as specified in the table “Programs for Crabgrass Control.”

A spring application may follow this fall application to provide season-long weed control but in no case must the maximum use rate per year be exceeded.

- Cool Season Grasses: Do not use Quali-Pro Dithiopyr 40 WSB on golf course putting greens consisting of creeping bentgrass.

- Bentgrass, Creeping: If Quali-Pro Dithiopyr 40 WSB is used on certain varieties of creeping bentgrass, such as ‘Cohansey’, ‘Carmen’, ‘Seaside’, and ‘Washington’, undesirable turfgrass injury may result. Since all varieties of creeping bentgrass have not been tested, use of Quali-Pro Dithiopyr 40 WSB is not recommended on all varieties. Do not apply this product to colonial bentgrass (Agrostis tenuis) varieties.

- Fescue, Fine: If Quali-Pro Dithiopyr 40 WSB is used on certain varieties of fine fescue, undesirable turf injury may result. Since not all varieties of fine fescue have been tested, use of Quali-Pro Dithiopyr 40 WSB is not recommended for use on certain varieties. Some fine fescue varieties have been found to be sensitive to this product including ‘Atlanta’, ‘Banner’, ‘Beauty’, ‘Bilgart’, ‘CF-2’, ‘Enjoy’, HF-93’, ‘Highlight’, ‘Ivalo’, ‘Jamestown’, ‘Koket’, ‘Majenta’, ‘Mary’, ‘Pennlawn’, ‘Tamara’, ‘Tatjana’, ‘Waldorf’, and ‘Waldina’.

- Bermudagrass: Turfgrass injury may result if this product is used on the ‘Tifgreen’ (328) hybrid of bermudagrass and use of Quali-Pro Dithiopyr 40 WSB on this species is not recommended.

- Buffalograss: For seedling Buffalograss, use this product only after the spring of the first year of turfgrass establishment and once the turfgrass is fully green and has established new roots.

Note: Except for crabgrass up to tillering stage of development, other emerged broadleaf weed or grasses are not controlled by Quali-Pro Dithiopyr 40 WSB. For optimum control of crabgrass, ensure that the treated area is free of weeds before application.

- Annual Poa (Poa annua) in South and coastal South Regions is controlled for longer periods of time if Quali-Pro Dithiopyr 40 WSB is applied at 1.25 lb/acre (0.5 lb ai) 6 weeks before overseeding and then applied a second time at a rate of 0.625 to 1.25 lb/acre (0.25 to 0.5 lb ai) 120 days after over seeding. Overseeded perennial ryegrass may be injured (See “Reseeding, Overseeding or Sprigging” precautions).

Restricted Entry Interval

12 hours