Common bermudagrass (Cynodon dactylon [L.] Pers.) is a warm-season perennial turfgrass common throughout Louisiana. Bermudagrass is often used as a desired turfgrass in lawn settings. However, when it invades other desired turfgrasses, such as St. Augustine grass, centipedegrass or zoysia, it must be treated as a weed. Bermudagrass is adapted to a wide variety of soil types. Because of its aggressive nature and tolerance for heat, drought and high volumes of traffic, it can be difficult to control in lawns.
Common bermudagrass is low-growing and has compact light- to dark-green leaves. Its leaves are fine-textured and sharply pointed and generally have a ring of small white hairs at the base where they meet the stem. The flower stems usually have three to seven spikes (stems of clustered flowers) with tiny pink to purple flowers. Common bermudagrass has robust stolons (aboveground stems) and rhizomes (underground stems), which can root and spread laterally.
For more information on Common bermudagrass identification and characterization visit the USDA Plants Database at https://plants.usda.gov.
The best way to prevent or reduce weed encroachment is to maintain a healthy lawn through regular mowing and proper fertilization and soil pH management. Properly maintaining a lawn through these cultural practices promotes dense and vigorous turfgrass and allows the turfgrass to better compete with weeds. For example, mowing St. Augustine grass lower than the recommended mowing height will give a competitive advantage to common bermudagrass, which is tolerant of low mowing. Below are the recommended mowing heights and nitrogen fertility rates recommended for each turfgrass species. In addition to these lawn care practices, hand removal of bermudagrass may also be necessary with less severe infestations.
In addition to improved cultural practices, herbicide applications may be required to achieve effective weed control. Common bermudagrass infesting centipedegrass can be suppressed by applying sethoxydim. A herbicide containing fenoxaprop and triclopyr will suppress common bermudagrass that is infesting zoysia grass. When using any type of herbicide, you must follow the manufacturer's labeled directions.
There are no effective selective herbicide options for managing common bermudagrass in St. Augustine grass. For St. Augustine grass and other turfgrass species with severe common bermudagrass infestations, a non-selective herbicide, such as glyphosate, should be applied to kill all vegetation, followed by site preparation and new sod installation at least two weeks after the glyphosate application.
For more information regarding pesticides for turfgrass please reference the Louisiana Suggested Chemical Weed Control Guide.
For information regarding weed identification and control options please contact your local LSU AgCenter Extension Parish Office. To find your local LSU AgCenter Extension Parish Office visit here.