YIELD AND NUTRITIVE VALUE OF EASTERN GAMAGRASS (TRIPSACUM DACTYLO1DES L.) HARVESTED AT TEN STAGES OF MATURITY.

摘要

Yield of 'Pete' eastern gamagrass (EGG) (Tripsacum dactyloides L.) was evaluated at University of Arkansas Forage Research Farm in Fayetteville, AR. Forage samples were harvested at 7-d intervals beginning on May 15 and ending on July 17, 2000. As EGGmatured, there was an increase (P<0.05) in height (from 36.7 to 88.6 in), tiller density (from 7.4 to 43.9/ft~2), and DM yield (from 1111 to 8944 lbs/ac). Leaf tissue comprised between 59.9 and 83.2% of the forage dry matter (DM) over the sampling period; conversely, stem tissue accounted for only 15.9 to 23.7% of the plant DM. Neutral detergent fiber (NDF) increased with plant maturity in whole-plant samples from 68.3 to 78.4%; similarly, acid detergent fiber (ADF) increased from 38.8 to 49.6% duringthe same time period. Concentrations of CP declined from 14.6 to 5.7% as plants matured. With limited fertilization (50 lbs N/ac), EGG demonstrated a tall growth habit, excellent DM yields, and a high proportion of leaf within the canopy.