How to Kill Palmetto Bushes
- 1). Select an herbicide containing glyphosate for killing a palmetto bush, recommends the Washington State University Extension. Choose an undiluted, water-soluble formula. This will be more effective than oil-soluble esters.
- 2). Spray the herbicide evenly on the bush foliage. This foliar treatment may be used on bushes up to 15 feet tall.
- 3). Cover the bush from all sides with herbicide, but do not drench the leaves to the point of runoff. Avoid using glyphosate on very hot days or on plants that are severely drought stressed.
- 4). Avoid spraying the plant if there is a chance of rain within six hours of application. Though you can use glyphosate at any time of the year, the most effective time is during August and September. Repeat treatment in seven to 10 days.
- 5). Cut down the dead bush with an axe. Use a stump grinder to grind the stump to a depth of 1 foot below the soil line.
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