Influence of fertilizer, aspect, and harvest date on chemical constituents and in vitro digestibility of tall fescue

Abstract

The nutritional benefits of fertilization on Ozark forest range for the late spring and summer period are questionable. Fertilizer application did not enhance either protein or calcium content, but did increase phosphorus. Acid detergent fiber (ADF) increased on fertilized plots while in vitro dry matter digestibility (IVDMD) decreased. An interaction between harvest date and fertilizer treatment revealed higher IVDMD for fertilized plots in May, but the relation then reversed for the remainder of the study. Harvest date proved to be the most influential treatment in the study. The changes associated with harvest date reflect the normal phenological development of tall fescue. The forage becomes less nutritious and less digestible as it approaches maturity and dormancy in July and August. Aspect significantly influenced ADF content and IVDMD. ADF content was lower and IVDMD higher on south-facing slopes.