Surface portions of the plants are damaged, but they quickly recover and density can increase. Glyphosate is relatively safe for humans and the environment and it breaks down rapidly. Remember that even though glyphosate is relatively benign in the environment, it will kill any plant it touches, including grasses and trees, so apply it very carefully. One method of application is to wear rubber gloves and apply it with a sponge or with a cloth glove worn over the rubber glove and dipped directly into the solution. Mix the concentrate according to label directions.
Herbicides containing triclopyr can also be useful.
When using any pesticide, be sure to read all label instructions and follow them carefully. Wear necessary protective clothing and equipment. Extension Services of Oregon State University. Corvallis, OR 97331-0817. Thomson, W.T. 1996.