Seasonal Changes in Forage Regrowth Yield and Quality of Three Old World Bluestems

Little information is available on differences in regrowth yield and quality among Old World bluestems (Bothriochloa spp.). Harvesting was staged such that 4-week regrowth of Caucasian (B. caucasica), cv. WW-Iron Master (D, ischaemum var. i.,ischaemum) and cv, Super Cauc (D. caucasica) was harvested each week from early May through mid-September to determine forage yield, ill vitro dry matter digestibility (IVDMD) and crude protein content of leaves and stems. Forage yield peaked in late June with WW-Iron Master, Caucasian, and Super Cauc producing 1280, 11S0 and 930 kg/ho/4 weeks of leaves and S00 200 and 160 kg/ha/4 weeks of stems, respectively. Leaf IV DMD and crude protein of WW-Iron Master· averaged 3.8 and 2.0 percentage units higher than that of Caucasian and Super Cauc during May and June. Leaf IVDMD of Caucasian averaged 2 percentage units less than Super Cauc and WW-Iron Master from mid-June through mid-August. Stem IVDMD and crude protein of all bluestems averaged only 1.5 and 3.0 percentage units less than that of leaves.