The aim of this study was to compare chemical composition, relative feed values, and in vitro true digestibility the giant fennel (Ferula communicus L. -F), helis (Prangos ferulacea -H), gum- tragacanth (Astragalus microcephalus WILD. -G) leaves oak tree (Quercus robur -O), a naturally growing plant on high- altitude plateaus Eastern Anatolia, with those alfalfa. In digestibilities (IVTD) rough...