Nitrogen Fertilization and Moderate Accumulation Intervals Can Maximize Stockpiled Warm-Season Forage Grasses

Stockpiling warm-season perennial grasses for grazing during the fall and early winter months is a management practice that can help reduce feeding and supplementation costs. Two seeded bermudagrass [Cynodon dactylon (L.) Pers.] and two bahiagrass (Paspalum notatum Flugge) cultivars were compared in a field trial in east-central Mississippi. Plots were assigned a single N application (0, 24, 56, and 84 kg N ha(-1)) and were sampled at 30 d accumulation intervals from September to December in 2015 to 2017 to monitor accumulated dry matter (DM) and nutritive value (crude protein [CP], acid detergent fiber [ADF], neutral detergent fiber [NDF], and total digestible nutrients [TDN]). Accumulation interval had the greatest influence on DM yield and CP. Forage mass was severely reduced (<527 kg DM ha(-1)) in 2016 due to widespread drought. In years with more rainfall, forage mass was >1200 kg DM ha(-1). Across all years, DM yield was influenced by forage species and cultivars within species, however no entry was consecutively greater than any other cultivar or species. Crude protein concentrations increased in 2015, and decreased in 2017 as the season progressed. The ADF and NDF concentrations increased with time for all entries. Total digestible nutrients declined as interval increased, with all cultivars recording <50.5 g kg(-1) across all years. In years with ample fall moisture, the combination of N application, followed by an accumulation interval between 60 and 90 d can provide adequate amounts of quality standing forage, regardless of cultivar, for extending the grazing season.