Yield and Quality of Creeping Bluestem as Affected by Time of Cutting

Abstract

Creeping bluestem (Schizachyrium stoloniferum Nash.) is a rhizomatous native grass that is the dominant species on many Florida rangelands. To evaluate its grazing potential, dry matter yield, in vitro organic matter digestibility (IVOMD), crude protein, neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL), were measured in plants cut at 10 and 20 cm stubble heights during 70-day intervals from June to October (summer), August to December (summer-fall), and October to February (winter). Winter yields were significantly greater (2,090 kg/ha) than summer yields (1,600 kg/ha) with summer-fall yields intermediate (1,860 kg/ha). After 3 years there was a significant decline in dry matter in plants cut at 10 cm, but yield was sustained in plants cut at 20 cm. Herbage regrowth in July to August was high in IVOMD (37.8%). Crude protein and IVOMD percentages were also greater in November to December regrowth (7.5 and 36%, respectively) and January to February regrowth (6.8 and 37%, respectively). However, since forage yield was lowest at the time, yield of protein and digestible organic matter were lowest. Percent NDF, ADF, and ADL were not greatly affected by initial growth or regrowth periods and averaged 80.0, 42.3 and 5.8%, respectively. Creeping bluestem may be one of Florida's greater yielding native grasses, but will require protein and energy supplements to provide good livestock performance.