Mixing Tips For Lesco Prosecutor Herbicide And What It Is

Dealing with herbicides is one of the least enjoyable parts of agronomics and landscaping. A lot of people, it seems, are not fans of the math behind some measurements. As such, brands with easy-to-follow guidelines always have an edge over the competition.

Lesco Prosecutor is an herbicide made up of 36.5% glyphosate. This equates to 4.17 pounds per U.S. gallon. It is classified as a Group 9 herbicide that is regulated by government safety standards. In order to use the product, the person applying it must be a certified commercial applicator.

Today we will be looking at Prosecutor, Lesco’s flagship herbicide, and its recommended measurements and applications. We will discuss what the product is (chemically-speaking), how it works, and its overall effectiveness. 

By the end of the article, you will have gained a clearer understanding of how to safely apply one of the most popular herbicides on the market.


What is Lesco Prosecutor?

Lesco is one of the most recognizable names in the world of agronomics and related equipment. The Ohio-based brand’s success, largely built on its game-changing fertilizers, speaks for itself.

Lesco dabbles in fertilizers, seeds, specialty equipment, general equipment, and soil control products. Herbicides fall under the last category and in Prosecutor, Lesco has one of its top-selling agronomic products.

Prosecutor is a “non-selective foliar systemic herbicide for weed control”. That means that it kills any plant it is applied to without discrimination. Prosecutor is made up of 36.5% glyphosate or about 4.17 pounds per U.S. gallon. As a result, it is classified as a Group 9 herbicide.

At the heart of this power is glyphosate, the key ingredient in many other herbicides (namely RoundUp).

How Is Lesco Prosecutor Classified

You see, herbicides are grouped according to their chemical structures and, by extension, their effect on a plant’s biology. In simple terms, certain structures result in certain effects. These effects are known as “action modes” in the scientific community.

Group 9 herbicides are known as aromatic amino acid inhibitors. This means that glyphosate disrupts functions that facilitate the creation of amino acids.

More specifically, glyphosate prevents 5-enolpyruvylshikimate-3-phosphate (aka EPSP), an enzyme involved in the production of key metabolic and growth amino acids such as tryptophan, tyrosine, and phenylaniline. When this happens, a non-resistant plant will no longer be able to process nutrients and will eventually wither and die.

Lesco Prosecutor And Glyphosate

We say “non-resistant” because some crops have been genetically modified to be resistant to the effects of glyphosate to make the non-discriminate herbicide’s application easier. Corn, canola, and soy are the most common crops in this particular regard, mainly because of the economic devastation wrought by weeds in the past.

Glyphosate used to be applied to the soil directly for weeds to take up through their roots. However, this poses a direct risk to desirable soil microbes as well as plants you may not wish to kill. 

As a result, this practice has been largely replaced by spraying glyphosate solutions directly onto leaf surfaces. Glyphosate contains surface-active agents or surfactants which break down protective cuticle membranes on a leaf surface.

Once past the leaf membrane, the glyphosate will spread to veins and, eventually, the plant’s main transport tubes. In addition to blocking amino acid production, glyphosate also moves towards the roots via the sap stream and causes chelation of surrounding soil nutrients. 

Chelation is a chemical bonding process that makes these nutrients insoluble and, thus, impossible for the plants to absorb.

We won’t go too deep over the well-documented controversies of glyphosate, of which there are several. The name has become such a hot topic that many manufacturers have turned their back on the chemical and have sought organic-based formulas instead.

Clearly, glyphosate has the potential to cause harm to humans, animals, and plants that interact with or are close to weeds that have had glyphosate applied to them. As such, great care needs to be taken when dealing with glycine-based herbicides, including when measuring dilutions.

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Lesco Prosecutor Safety

Lesco Prosecutor comes with (physical or digital) instructional guides on how to use the product safely and effectively. Connecticut College has one of these handy guides for Lesco Prosecutor Professional MAX and its application via ground or air.

Safety is the overriding theme throughout the guide and this starts right at the label and the First Aid guide behind it.

There are also recommended personal protection protocols, specifically over protective clothing. Individuals working with the product must wear long-sleeved tops and bottoms, shoes and socks, as well as chemical-resistant gloves that are waterproof. Polyethylene or polyvinyl gloves are the most common. 

While personal protection is highly recommended for all applications, it is enforceable under federal law when it comes to large-scale agricultural applications. There is also the Worker Protection Standard that mandates the provision of protective clothing as well as adequate training for chemical use.

Application is also covered in the guideline, which recommends that “protective handlers” are the only people who may be in an application area at any given time. After application, the Worker Protection Standard also requires a restricted entry interval of 12 hours for any treated area. This simply means that workers should not be compelled to enter treated areas during this interval.

The Worker Protection Standard doesn’t apply to non-agricultural or domestic uses. However, it would be wise to adhere to the same principles. Place warning signs and keep kids and pets away from the site for at least 24 hours. Dogs are particularly prone to allergic reactions to glyphosate, so take heed.

Interestingly, private residents cannot apply Lesco Prosecutor on their yards unless they are certified “commercial applicators”. This is because of the fear of poor application or disposal habits that could result in negative impacts to soils or even local water supplies.

Prosecutor Storage

Storage is also an important part of getting the best out of liquid herbicides. Lesco Prosecutor must be stored in a cool dry place away from direct sunlight. We highly recommend keeping it in its original container as the plastic is designed to maximize the product’s shelf life. The product can last for up to five years in the right conditions.

How Long Does Prosecutor Herbicide Take To Work?

So, if this is one of the most efficient products on the market to kill unwanted plants, how long does prosecutor take to work?

Lesco Prosecutor takes anywhere from 12-24 hours for visible results. A clear sign is yellowing and shriveling leaves as the plant weakens. Within 48-72 hours plant should begin to shrivel and wither into the soil. The total time until plants are gone from sight could be as long as one week.

There are other factors as well. It is recommended that no water or rain saturate the plants for that same period of 12-24 hours. Other factors include temperature, air humidity, and application density.

Lesco Prosecutor Mixing Ratio

So, what’s the best way to use Lesco Prosecutor safely and effectively?

Well, the first step is to know the specific concentrations to use on your targeted weed species. The second is to dilute the product accordingly.

Luckily, Lesco product guides cover this too, so you can eliminate the risk of wastage or ineffective solutions.

Lesco provides limits known as “maximum use rates”. Basically, you must not exceed 6 lbs. of glyphosate acid per acre per year on agricultural use sites. For non-agricultural use areas, 8 lbs. of glyphosate acid per acre per year is the limit.

The actual dilution depends on the type of weeds you’re dealing with. Different weeds require different volume per volume (v/v) solutions of Lesco Prosecutor to control or suppress them. This value is often expressed as a percentage of the water volume it is diluted with.

Annual weeds which grow to heights of less than 6 inches can be dealt with by solutions in the 0.4-0.7% range. Weeds over 6 inches require 0.7-1.1%. Perennial weeds may require 0.7-1.5%. The Lesco guide has more in-depth charts for specific weed and grass species.

The following table shows the ideal dilution ratios for different scales of application. We have highlighted the amounts of Prosecutor (in fluid ounces) to use to obtain a specific v/v value. The water volumes are in gallons.

v/v1 gal10 gal25 gal100 gal
0.4%0.5 fl. oz5 fl. oz12 fl. oz3 pints
0.7%0.9 fl. oz9 fl. oz1.4 pints5.6 pints
0.9%1.2 fl. oz12 fl. oz1.9 pints3.8 quarts
1.1%1.4 fl. oz14 fl. oz2.2 pints4.4 quarts
1.5%1.9 fl. oz1.2 pints3 pints1.5 gallons
2.2%2.8 fl. oz1.8 pints4.4 pints2.2 gallons
5%6.4 fl. oz4.0 pints10 pints5 gallons
10%12.8 fl. oz1 gallon2.5 gallons10 gallons

As you can see, to achieve a 1.1% solution, you should mix 1.4 fl. oz of Lesco Prosecutor in with one gallon of water. To achieve the same concentration with 100 gallons of water, you must mix in 1.5 gallons of Prosecutor.

The Final Touches On Lesco Prosecutor Herbicides…

All herbicides should be handled with care, but they are the most effective form of weed control on the market.

Keep in mind that due to regulations that are becoming more and more strict, some of these are not usable by anyone without a license. These certifications like the trend in many things today are in the name of safety.

Though safety can be and is taken to extremes in our modern society, in the case of chemicals like these there is some merit in using proper procedures and caution.

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Mathew Booe

Mathew has worked in landscaping professionally for over 10 years. He is a grandpa and frequently interviews other experienced landscapers and lawn care experts who are also grandpas for these articles.

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