Annual Ryegrass Spring Removal and Regrowth of Tifton 85 Bermudagrass.

Overseeding of ryegrass into warm-season grasses is favored because of its high quality and early yield. In some years, field observations have shown stand reduction and slow spring regrowth of Tifton 85 bermudagrass (T-85) associated to competition for resources from ryegrass growth. Three ryegrass removal dates (early March, D1; mid March, D2; and late March, D3) and three removal methods (chemical, C; mechanical, M; and simulated grazing, G) plus two controls (T-85 not overseeded, and T-85 overseeded with ryegrass but no removal) were tested on different variables (T-85 cover, light interception, soil temperature, DM yield, and carbohydrate reserve) to examine the competition dynamics of these two grasses. Only T-85 cover and light interception is reported. Results show that T-85 cover is affected by removal method (P < 0.01). Greater T-85 cover in early spring (March-April) occurred with herbicide (36%) followed by simulated grazing (21%), and mechanical (12%) ryegrass removal. Light interception at soil level was affected by removal date (P = 0.09) and removal method (P < 0.01). Highest light interception occurred with early removal date (D1; 52%) followed by D2 (50%), and D3 (45%). Implications from this study show that warm spring temperature will require early removal of ryegrass to guarantee T-85 bermudagrass regrowth in the spring.