INFLUENCE OF HARVESTING MANAGEMENT ON REGROWTH PERFORMANCE AND NUTRITIVE VALUE OF EASTERN GAMAGRASS

摘要

Yield and nutritive value of regrowth from a 2-yr old stand of 'Pete' eastern gamagrass (EGG) (Tripsacum dactyloides L.) regrowth was evaluated at University of Arkansas Forage Research Farm in Fayetteville. Forage samples were harvested at 2-wk intervals beginning on July 11, 2001. Measurements were taken on the regrowth at cutting intervals of 4-, 6-, 8-, and 10-wk after initial harvest. From wk 4 to 10 plant height, number of tillers, and yield of dry matter (DM) increased. Dry matter yields were1098, 2172, 3848, and 5470 Ib/acre on wk 4, 6, 8, and 10, respectively. There was an increase in content of neutral detergent fiber (NDF) and acid detergent fiber (ADF) from 61.1 to 71.4% and from 29.6 to 37.0%, respectively. There was an increase of acid detergent lignin (ADL), hemicellulose (HEM), and cellulose (CELL) from 7.4 to 10.2, 31.5 to 34.4 and 22.2 to 26.8%, respectively. Crude protein (CP) concentration decreased over time from 16.1, 12.4, 8.2, to 7.8% after 4, 6, 8, and 10 wk of regrowth, respectively. Results from the regrowth study indicated that the optimum time for harvesting EGG is between 6 and 8 wk after the initial harvest.