The population growth and spatial distribution of threeDalbulusleafhopper species were monitored on maize (Zea maysL.) from the seedling stage through maturation and senescence under greenhouse conditions.D. maidis, a maize specialist, completed two generations before maize senescence, with a significant population increase between the first and second generation. F1nymphs and adults moved upward on leaves (vertically) and from outer leaves into whorls (horizontally) soon after eclosion.D. gelbus, a gamagrass (wild maize relative) specialist also found on maize in the field, completed two generations on maize, but with a significant decrease in population size between generations.D. gelbusmoved upward on leaves as F1nymphs and adults, but not into whorls as frequently asD. maidis. D. quinquenotatus, a gamagrass specialist, produced one generation on maize, with population extinction occurring soon after adult eclosion on post-anthesis maize. Nymphs and adults remained within protective leaf sheaths of lower leaves, and did not move upward on leaves or into whorls. Some individuals moved onto tillers developing at the base of maize stalks. Utilization of the whorl is suggested to be critical in establishing a large second generation before maize senescence. Differences in the behavioral responses ofDalbulusspecies to maize phenology may explain, in part, the observed field host associations, and influence pest potential ofDalbulusspecies.