Benomyl was applied singularly or combined with paraquat to xylary tissue either on a strip of exposed xylem or in a tangential bore hole. Blue stain infestation was assayed from wood disks collected at five different levels above the treatment area of each sample tree. Oleoresin accumulation was analyzed at 15 and 60 cm above the treatment area. Blue stain was not controlled by benomyl in paraquat treated trees. However, benomyl increased resin acid yields in paraquat and nonparaquat treated trees 20 and 270%, respectively. Resin acid accumulation increased and tree growth losses decreased when paraquat plus benomyl was applied to exposed xylem. For. Sci. 33(2):552-557.