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Mistery Grass killer?

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From: Stephanie Z
Jacksonville, FL
We have Saint Augustine grass, which has been dieing over the past four weeks. The grass has been green for almost five years. Yet recently my husband hired a fertilizing company to make it greener for the sale of our house.

After the first application of fertilizer we had lots of weeds come in so I call the company to fix the weed problem. After they sprayed for the weeds the grass started to die turn yellow and purple on the blades, with huge brown areas of completely dead grass. When I called the company while on vacation one guy said he had a look at the grass and said it was getting too much water. After returning the problem was worse, once again an employ came out to check the grass and said the grass was not getting enough water. This is after a tropical storm for a few days and watering three times a week for 30 minutes. Then I called to speak with a supervisor. He came out to the house and told me the same thing our grass was not getting enough water. When I put my finger in the soil it was very damp. He even took a twelve inch sample of soil and you could see it was damp all the way through. Then he said that the roots weren’t good and were not able to take up the water. Now I see that we also have lost a large tree where they notably sprayed and grass is also dieing.

Do you think we have a chemical burn or the weed killer was too strong and how do I prove it to a company that doesn’t fess up? I just want my green grass back so I can sell my home. Everyday the grass gets worse.

Extension Message
From: Douglas B. Gucker
Extension Educator, Local Food Systems and Small Farms
DeWitt/Macon/Piatt Unit

I apologize for my delay in getting back to you. I live way up in Illinois, so I have had to do a little research on St. Augustine grass. It does not grow up here.

Yes, your thought that your grass has a herbicide problem could be correct. According to information from Oklahoma State, Mississippi State, Alabama, & Univ. of Georgia, the phenoxy herbicides need to be used very carefully on St. Aug grass. This class of herbicides is used very commonly to control broad-leafed weeds (i.e. - not grassy plants). The herbicides in this class include: 2,4-D; dicamba & MCPP. According to the literature, these herbicides can discolor and weaken a St. Augustine grass stand. ( Another herbicide commonly used to control grassy weeds in turf is the organic arsenicals. This class of herbicides will seriously damage St. Augustine. Herbicides in this class include: CMA, DSMA & MSMA. (

How can you determine if any of these products were used on your grass? Check the bill from the "Lawn care" company - it is supposed to show all products that were used on your lawn and their application rate. Testing laboratories can detect trace amounts of herbicides in the soil, but these are usually expensive tests. A & L Laboratories can do an analysis for the phenoxy class. ( - $250/sample

Have you contacted your local extension office in Jacksonville? They are located at: 1010 N McDuff Ave., Jacksonville, FL 32254-2083 (904) 387-8850

Hope this is helpful-

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