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Crop and Pest Management Guidelines

A Cornell Cooperative Extension Publication
Page Contents
44767

*Dimension

Common Name: dithiopyr

Formulations: 2EW, 40WP, others

Uses: Selective preemergence control of summer annual grasses and broadleaf weeds in turf and landscape ornamentals. *Dimension Ultra 40WP and 2EW also for use in noncropland, industrial sites, and container or field-grown ornamentals. Postemergence control of crabgrass is possible when applied before crabgrass has tillered.

Amount of active ingredient

Amount by formulation

2EW

40WP

Per Acre

0.25 lb.

1 pint

10 oz.

Per 1,000 sq. ft.

0.37 fl. oz. (2.2 tsp.)

0.23 oz. (2 pkts.)

NOTE: In NYS, no more than two pints (0.5 lb. AI) of *Dimension 2EW, and no more than 20 oz. (0.5 lb. AI) of *Dimension Ultra 40WP may be used per year per acre. In Nassau and Suffolk Counties of New York, do not exceed one pint (0.25 lb. AI) *Dimension 2EW and no more than 10 oz (0.25 lb AI) of *Dimension Ultra 40WP per acre per year. Check current NYSDEC listings and product labels for maximum use rates and other restrictions in NYS and in Nassau and Suffolk Counties.

Major Weeds Controlled: Preemergence control of Japanese Stiltgrass, crabgrass, goosegrass, annual bluegrass, speedwell, lespedeza, bittercress, chickweed, and henbit. Higher rate is needed for goosegrass and broadleaf weeds. Postemergence control of smooth and large crabgrass if applied before tillering.

Major Weeds Not Controlled: Weeds that are established. Weak on many broadleaf weeds.

For Best Results: Apply as directed spray to tolerant established ornamentals. Some over-the-top application on selected species is allowed (see label). Apply before weeds have emerged. Activate with 0.5 inches of rainfall or irrigation. Two applications are generally necessary for full-season grass control.

Cautions and Precautions: Over the top applications may injure the foliage of ornamentals (see labels). In landscape beds, apply *Dimension as a directed application, avoiding contact with foliage of ornamental plants. Safe on most cool- and warm-season turfgrass species if well established; consult label for variety and species restrictions.

Residual Activity: Two applications are necessary for full-season grass control.

Volatility and Leaching Potential: Moderately high volatility. Incorporation via irrigation is necessary. Leaching is negligible.

Symptoms and Mode of Action: Inhibits root growth by blocking cell division in a manner similar to nitroanaline herbicides, but the exact site of action is different.

Manufacturer: Corteva Agriscience

EPA Reg. Nos.: *Dimension 2EW: 62719-542

*Dimension Ultra 40WP: 62719-445

*Restricted use pesticide.

†Not for use in Nassau and Suffolk Counties.