Bermudagrass decline is characterized by gradual thinning or outright loss of bermudagrass stands over time. Below are some of the reasons associated with bermudagrass decline:
1. Fertility: The lack of an appropriate fertility program may be the number one cause of bermudagrass decline. Nitrogen (N) is important for forage production, however, it is often the only nutrient applied. Phosphorus (P) and Potassium (K) are critical for forage production and persistence. Potassium (K) has been shown to be an important nutrient for forage, stolon and rhizome production. It is also associated with improving bermudagrass tolerance to both winter kill and diseases such as Helminthosporium leaf spot. SOIL TESTING is a critical step in knowing what levels of nutrients are actually required.
2. Stocking Rate: Too heavy a stocking rate places excessive grazing pressure on forage resources. Heavy grazing pressure can reduce animal performance but just as importantly, can decrease plant vigor. A reduction in plant vigor reduces plant growth and can be a contributing factor in bermudagrass decline.
3. Overseeded Cool-Season Forages: Cool-season annual forages are often over-seeded into bermudagrass fields and provide excellent nutrition for cattle during the fall and winter months. An important aspect of overseeding cool-season annual forages is the timely removal of the forage in the spring prior to bermudagrass breaking dormancy. If the cool-season forage is not removed the result is intense plant competition for sunlight, moisture and nutrients. Excess ryegrass that cannot be controlled by grazing or harvested for hay should be sprayed during the warm-season perennial grass dormant season with glyphosate.
4. Drought: Reduced moisture results in reduced forage production. Even though we can not control mother nature we can follow best management practices (fertility, stocking rate, weed control, etc) during years of adequate moisture. Following best management practices can help to reduce the impact of drought. US Drought Monitor
5. Pests: Invasive weeds can dominate pastures and reduce the productive capability of bermudagrass. Weed identification is critical in order to determine the best time to control as well as what is the best herbicide to spray. Grasshopper and fall armyworm infestations can have a devastating effect on bermudagrass production in the summer and fall. These pests rob you of valuable forage for grazing or hay production. Scouting for these insects early and following with appropriate pesticides can reduce possible damage. As always follow the label of all pesticides, the label is the law.Suggestions for Weed Control in Pastures and Forages
For more information on Bermudagrass Decline.
Vanessa Corriher-Olson
Forage Extension Specialist
Soil & Crop Sciences, Overton, TX
Texas A&M AgriLife Extension Service
Texas A&M University System