How to Kill Smutgrass
- 1). Wait until between the months of June and September which is the time period that smutgrass is most effectively killed. Choose the month that receives the most rainfall in your area.
- 2). Open a garden sprayer and fill it with an herbicide containing hexazinone as the main ingredient. According to the University of Florida, the only effective herbicide containing this ingredient is called Velpar. Use 3 pts. for every one acre of land that you are treating.
- 3). Dilute the herbicide with water as instructed on the bottle directions. Place the top on the garden sprayer and shake it gently to mix the solution well.
- 4). Spray the entire ground surface with the herbicide solution until the grass blades and surface of the soil is saturated. Concentrate the herbicide on any visible clumps of smutgrass and cover all other areas as well.
- 5). Water the surface of the soil within two days of the herbicide application if no rainfall occurs. Water is required to soak the herbicide down to the root system of the smutgrass to kill it.
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