parasitic plant: plant living on another plant and obtaining organic nutriment from it
parasite: an animal or plant that lives in or on a host (another animal or plant); it obtains nourishment from the host without benefiting or killing the host
rhododendron: any shrub of the genus Rhododendron: evergreen shrubs or small shrubby trees having leathery leaves and showy clusters of campanulate (bell-shaped) flowers