Evaluating Yield and Nutritive Value of Tifton-85 Bermudagrass and Tifton-85 Bermudagrass-Alfalfa Mixtures As Baleage in the Southeast.

Though bermudagrass is the primary perennial warm-season forage in the Southeast, it requires high fertilization rates and often requires supplemental feeding to meet animal performance goals. Interseeding alfalfa into bermudagrass can reduce N fertilizer needs while improving forage quality, thereby reducing fertilization cost and the need for additional supplementation. Alfalfa-bermudagrass baleage can further improve profitability by reducing weather related losses associated with traditional hay production. The objective of this research is to compare the forage quality and yield of bermudagrass harvested as baleage with and without alfalfa interseeded. This study was conducted on an established field of ‘Tifton 85’ (T85) bermudagrass (Cynodon dactylon (L.) Pers. x C. nlemfuensis Vanderyst) at the University of Georgia Coastal Plains Experiment Station in Tifton, Georgia. Ten 0.5-ha plots were randomly assigned to either T85 or T85 interseeded with ‘Bulldog 805’ alfalfa (Medicago sativa L.; AB). The T85 treatments received nitrogen fertilization (84 kg N ha-1) four times throughout the growing season, and both treatments were irrigated to supplement rainfall. Plots were harvested at early bloom stage every 28 to 35 days, baled at 40-60% moisture, and individually wrapped. At each harvest plots were evaluated for botanical composition and forage yield. Bales were sampled prior to wrapping for nutritive value analysis. In the year alfalfa was established, T85 had significantly greater seasonal yield (P<0.001) than the AB treatments (12,299.7 ± 348.9 kg ha^-1 and 8,872.43 ± 348.9 kg ha^-1, respectively). However, in addition to producing harvestable forage further into the fall (AB produced a 6^th cutting in November), the In-vitro True Digestibility (IVTD) and the crude protein (CP) were significantly higher (P=0.035 and P=0.006, respectively) in the AB mixture (66.71 ± 2.01% and 60.24 ± 2.2%; 14.02 ± 0.6% and 11.44 ± 0.66%, respectively).