Bermuda Grass (cynodon dactylon) is a perennial grass native to tropical and subtropical Africa. It was introduced into the United States as a pasture and lawn grass it has become a popular choice as a lawn grass in the Phoenix Valley. Although well adapted to the heat, drought and alkaline soils of the desert Southwest, it takes over 40 inches of water a year to keep the grass looking green, despite the fact it is dormant throughout the winter. For this reason, it is desirable to keep the amount of lawn to a minimum. Removing an established Bermuda grass lawn takes persistence but is well worth the effort in water savings.
There is no one perfect chemical to remove such a persistent grass, but the most effective appears to be glyphosate. This chemical is sold under the brand names DOOMSDAY, KLEENUP, or ROUNDUP and could be available under other trade names. The herbicide is systemic, that is, it is carried through the plant's vascular system.
One week before application of the herbicide, water the lawn ever day for 30 - 40 minutes. This makes the grass grow actively. Do not mow at all.
Choose a windless day and apply the herbicide, carefully following all directions for use on the container. It is best to use a sprayer which has a small concentrated stream so that the application can be controlled. Adjust the nozzle of the sprayer to the heaviest possible spray to avoid drift onto other plants.
Cover plants which are not to be sprayed with a heavy layer of newspaper or plastic, or hold a board in front of them while spraying. Woody bark usually will not absorb the chemical, but leaves and tender shoots will.
Repeat the entire treatment after one week. The second time it is only necessary to water the lawn for three days prior to spraying. Two weeks after the second spraying, scalp the lawn with a mower set very low, or use a power rake. Take off as much grass as possible.
Within seven days of the first spraying, 90% of the grass should be killed. Within two weeks of the second spraying, 99% of the grass should be killed. Established Bermuda grass lawns can have root systems going down as much as three feet, and there could be re-sprouting in those areas. Once a month, spot treat any areas that show living grass.
The area can be replanted after the dead grass is removed. Take care not to mulch the treated areas for two to three months to be sure you have removed as much of the grass as possible. once mulch is in place, continue to spot treat every two or three months to control re-sprouting.
The Desert Botanical Garden