Monosodium methyl arsenate (MSMA) is an arsenic herbicide and is considered less toxic as compared to other inorganic forms of arsenates. It is used for selective control of grasses and broadleaves including crabgrass, summer grass, dallisgrass, sandburs, and much more. In 2009 the use of MSMA was cancelled on citrus orchards, parks, residential areas, any non-bearing fruit and nut trees and athletic fields.

The trade name of MSMA in the market include:

  • Target 6.6
  • Target 6 Plus
  • MSMS 6 Plus
  • MSMA 6.6 


This herbicide is registered by EPA (Environmental Protection Agency) for the use on golf courses, sod farms Highway Rights-OF-Way and cotton. 

There are multiple ways of using MSMA some of which include a spraying rig, hand pump-sprayer and backpack sprayer.

For more effective results, spray it when wind speed ranges from 2 to 10 mph and temperature between 70 and 90 degrees Fahrenheit.

Highway Rights-OF-Way

  1. No more than two broadcast applications per year.
  2. Avoid using around 100 feet of proximity to permanent water bodies.

Sod Farms

  1. Use only two broadcast applications per season as allowed.
  2. Avoid using it within 25 feet proximity of permanent water bodies.

Golf courses

  1. One broadcast application is permitted for newly constructed golf courses. 
  2. Spot treatment for 100 square feet per spot and must not exceed 25% of total golf courses for regular golf courses.


  1. Only allowed two applications per season.
  2. Avoid using pre-plant cotton.
  3. Avoid using more than a total of 4 pounds per acre per season.
  4. Do not use within 50 feet proximity of permanent bodies.

How to Mix MSMA Herbicide For better use

Most MSMA products come water-soluble. Fill half of the spray tank with water followed by the required amount of herbicide with agitation. Add some more water to fill the tank and apply the fields. Never store the spray solution inside the tank for a long time.

Why choose MSMA:

MSMA gathers in the root and leaf tips, rapidly killing the roots and stem tissues. It also interferes with the ATP production of plants impacting the weed growth. It usually rainfast within 3 hours of its application. Within 3-7 days of MSMA application, the infected weeds turn yellow to brown. MSMA is considered to be more effective on grass weeds as compared to broadleaf weed. 

When the weeds are still young, and in their growing phase MSMA has proven to work the best however, in harsh conditions such a drought, and cold temperatures weeds are doing through stress, so you may require to increase the dosage for the weeds to die. 

Weed Resistance:

A population of plants or weeds can easily develop natural resistance to MSMA if used in the same field again and again or in successive years as the only method for the control of weeds. The resistance process can be delayed if you stop using the product consecutively on the same weed species. 

Safety Concerns and Recommendations:

Using MSMA comes with its side effects. After application MSMA can become more toxic over time in the soil and contaminates it which can cause serious health effects to humans, plants and other microorganisms. It can contaminate drinking water which further increases the toxicity issues.

Before using MSMA make sure to wear a long-sleeved shirt and pants, chemical resistant gloves, goggles, and a mask because if it comes in contact with the human skin it can cause deleterious effects. Remove Personal Protective Equipment (PPE) immediately after using the herbicide and dispose properly. Wash everything thoroughly and then change into a fresh pair of clothing. Wash your hands properly before eating, drinking or using the toilet. 

Make sure to read that label thoroughly before you use any herbicide containing MSMA and follow the instructions properly. 


  • Always store this product in a cool and dry room away from any heat and ignition. 
  • Must be stored away in a secure room with a lock and key to prevent access from children or any other unauthorized person.
  • Make sure the container is tightly sealed when not in use.
  • Avoid storing near water, food items, seeds or any other pesticides


The waste of pesticides is very toxic and can cause harmful effects to the environment. Hence, they should be disposed of properly according to the instructions given on the label at the back of your product. If you are still not sure how to dispose of it then contact the environmental control agency of your state or hazardous waste representative at the closest EPA office for better guidance.

Avoid using or refilling a non-reusable container and offer it for recycling whereas when using a refillable container make sure you only fill it with the pesticide and do not use it for any other purposes. 

Preventive measures:

The best way to prevent the lumpy lawn is to avoid the cause by taking precautionary measures and controlling the problem creators. Furthermore, keep it a little overseeded in humid periods of the year, avoid playing active games like cricket, football, or badminton, keep your pets away from the lawn if they have scrapping habit, use pre-emergent herbicides in your lawn in the early springtime to avoid pest invasion, do not keep heavy furniture in the lawn, and never use a roller to level the lumps.

Hopefully, the above-mentioned techniques would work for all the lawn owners and gardeners. Do not forget to leave your valued response and share techniques if you have ever tried any other than described in the post, and succeeded to recover your lumpy lawn. 

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