Imazapyr

When there is a lot of broadleaf weed activity on your property, Imazapyr is an active herbicide that works well to get rid of these invasive plants. Solutions Pest & Lawn has a quality selection of herbicide products in stock that contain the active ingredient Imazapyr. We highly recommend this product to our customers who want to control broadleaf weeds.

On this page, you can learn some background about Imazapyr, its mode of action, and its benefits. You can also access this page to shop our recommended products containing Imazapyr.

What is Imazapyr?

Imazapyr is an herbicide from the dinitroaniline class and is used in pre- and post-emergent applications to control annual grasses and certain broadleaf weeds. 

The herbicide active ingredient is commonly found in two forms: weak acid and isopropylamine salt. Imazapyr is also an aquatic herbicide, having been registered with the EPA in 2003. 

Imazapyr is a systemic herbicide that is absorbed by the leaves and roots and moves rapidly through the plant.

How Does Imazapyr Work?

Mode of Action

Imazapyr’s mode of action works by inhibiting or stopping the synthesis of certain plant amino acids. These amino acids are crucial for DNA synthesis and growth.  Imazapyr is primarily absorbed through plant tissue but can also be absorbed through roots in the soil. 

Plants stop growing initially in the roots, and this moves up through to the above-ground parts of the plant. Complete death occurs one month, more or less, after treatment, depending on environmental conditions. 

Benefits of Imazapyr

Imazapyr is a great alternative to Glyphosate and has several advantages over Glyphosate, such as a quicker drying time. Manufacturers claim it is rainfast within 1 hour. This leads to a higher uptake of Imazapyr into the plant vs. Glyphosate. Imazapyr also remains active where applied until the plant absorbs it. Imazapyr also has lower spray volumes than Glyphosate, allowing more area to be treated.

Use Imazapyr as either a pre- or post-emergent control of broadleaf weeds, but preferable as a post-emergent as it is most effective when weeds have sprouted. It is also great for treating aquatic weeds on a water body such as a pond.

Drawbacks of Imazapyr

Plants treated with Imazapyr typically die slowly. Targeted plants take several weeks to months to show visible signs of damage. When weeds are particularly stubborn and persistent, it will feel like nothing is happening because they work slowly.

Do not use Imazapyr if you want to kill weeds quickly and don't have the patience for the active ingredient to do its job independently. You may be better suited for a faster-acting herbicide.

Is Imazapyr Safe?

Imazapyr is safe to use when applied according to label directions. Proper personal protective equipment (PPE) should be worn before handling or applying Imazapyr (or any of the other chemicals we carry). Gloves, goggles, and long-sleeved clothing should be the minimum standard. Please refer to the label for proper safety instructions.

What To Expect

Imazapyr is a slow-acting inhibitor that can take a few weeks to work. It is generally most effective during the target plant's post-emergence. In some cases, reapplication may be necessary to best control the target weed. Please refer to the label for specifics on application rates, interval time when reapplication is necessary, and any other vital info regarding the weed you wish to treat.

Featured Products

Imazapyr 4 SL Herbicide—Imazapyr 4 SL Herbicide is a pre-and post-emergent bare-ground herbicide for controlling unwanted vegetation in non-cropland areas and aquatic sites. It sterilizes the soil it is sprayed over, and nothing will grow for up to one year. Imazapyr Can also be used in pastures, rangelands, and other listed areas.

Ecomazapyr 2 SL Aquatic Herbicide—Ecomazapyr 2 SL Herbicide is formulated as a pre-emergent and post-emergent for controlling emergent and floating aquatic vegetation in aquatic sites and terrestrial habitats. It may also be used for cut stump, frill, cut stem, and girdle applications.