This work has shown that oil extracts from E. adenophorum possess fungitoxic activities that inhibit the growth of P. myriotylum, thereby increasing the possibility for using these oil extracts to control P. myriotylum in commercial crops in the future. The use of these oil extracts will also turn E. adenophorum from a weed to a valuable resource. Further studies are required to determine the stability of these oil extracts in the field and their phytotoxicity to a range of commercial crops.