Dithiopyr

Dithiopyr is an active ingredient used in pre-emergent herbicides that kill a variety of broadleaf weeds and grassy weeds. One of the common uses of Dithiopyr is to prevent crabgrass from emerging on lawns in the springtime.

Solutions Pest & Lawn has several products in our herbicide inventory that contain Dithiopyr, and we highly recommend this product to our customers who deal with recurring weeds every growing season. On this page, you can learn some historical facts about Dithiopyr, how it works, and its benefits. You can also access this page to shop our entire line of dithiopyr-containing products.

What is Dithiopyr?

Dithiopyr is an active ingredient found in several pre-emergent herbicide products.

Dithiopyr is a tan solid with a sulfur-like odor, and it is formulated into liquid, powder, and granular herbicide formulations.

Dithiopyr is used for pre-emergent control of summer annual grasses in turf, including bentgrass, landscape beds, containers, and field nurseries. It can also be applied before crabgrass has been tilled to achieve post-emergent control.

How Does Dithiopyr Work?

Mode of Action

Dithiopyr’s mode of action is that it acts as a root growth inhibitor, causing roots to stop growing and mitotic cell division to halt. It interferes with the formation of microtubules and spindle organizing centers. In other words, Dithiopyr controls weeds by disrupting microtubules, which are necessary for plant growth, rendering the target weeds unable to grow. 

Benefits of Dithiopyr

When applied at prime times before weeds typically grow, Dithiopyr effectively prevents the growth of control of crabgrass, goosegrass, chickweed, spurge, and Poa annua. Dithiopyr is commonly used for both residential and commercial lawns.

Dithiopyr-based products have also been proven effective for use on golf courses, sports turf, landscape ornamentals, container- and field-grown nursery ornamentals, commercial sod farms, and non-crop areas, including roadsides.

Drawbacks of Dithiopyr

It is important to make the distinction that pre-emergent herbicides do not destroy weeds entirely but rather prevent growth, a sort of birth control if you will.  That is why they must be applied annually to retain the desired effects. If a weed you target has already risen from the soil, using a Dithiopyr-based product will not effectively eliminate the plant.

Is Dithiopyr Safe?

Dithiopyr is safe to use when applied according to label directions. Always read the product label for safety instructions when handling Dithiopyr.

We recommend using safety equipment such as gloves, protective goggles, a breathing mask, and long-sleeve clothing when handling Dithiopyr products or any chemical herbicide active ingredient.

What To Expect

Dithiopyr depends on the proper timing of applications, such as in the early spring and fall seasons. This is because the pre-emergent active ingredient only works on weeds that have not yet sprouted. When applied at the right time, Dithiopyr can control weeds for up to 16 weeks. 

Read the label carefully for application instructions and the correct application rate for your problem weed. 

Featured Products

Dithiopyr 2EW Herbicide—Dithiopyr 2EW Herbicide (generic Dimension EW herbicide) from Quali-Pro is a pre-emergent and post-emergent herbicide for controlling grassy and broadleaf weeds in established turf and ornamentals. Its low mix rate and non-staining formulation make it a great alternative to prodiamine.

Dithiopyr 40 WSB Pre-Emergent Herbicide—Dithiopyr 40 WSB (Dimension herbicide) from Quali-Pro is a non-staining pre-emergent herbicide for the control of grassy weeds in established turfgrasses. The product comes in easy-to-use measured pouches and works well in commercial applications.