The fall armyworm, Spodoptera frugiperda (J. E. Smith), is susceptible to at least 16 species of entomogenous pathogens including viruses, fungi, protozoa, nematodes, and a bacterium. Many of these occur naturally in fall armyworm populations. Some cause natural epizootics. The few attempts to suppress fall armyworm populations on agricultural crops by application of pathogens have had various degrees of success.