NUTRITIVE VALUE OF COOL SEASON FORAGES OVER TIME IN A CONIFER WOODLOT WITH VARYING LEVELS OF LIGHT INTENSITY

摘要

The Appalachian region contains numerous small farms made up of both open pasture and woodlots. A common problem is the loss of forage quality and quantity during the summer period due to high temperature and low rainfall. Introduction of forage species within woodlots offers promise of improved forage availability, higher forage quality and increased farm income. Nutritional value of herbage grown under a conifer tree canopy was evaluated in relation to percent available light and season. Forage crude protein was influenced by available light (P<0.05) and was highest within the 50% available light areas (27.06 %) and lowest within the 80% available light areas (24.07). Forage metabolisable energy was not affected by light level (P>0.50). Forage nitrate was also affected (P<0.05) by available light and mirrored crude protein values. Nitrate content reached toxic levels within the 20 and 50% light areas (0.25 and 0.35% respectively). Total nonstructural carbohydrates were highest (P<0.05) within the80% light area (5.33%). Harvest date also affected (P<0.05) nutritional parameters. Forage nutritive value estimates suggest that low light conditions may negatively impact nutritive value, especially concerning forage nitrate content. More research isneeded to improve our understanding of the plant-soil-animal interactions in silvopastoral systems.