Pheromone traps of 7 designs were tested against natural populations of the fall armyworm, Spodoptera frugiperda (J. E. Smith), and the beet armyworm, S. exigua (Hübner). (Z)-9-dodecen-1-ol acetate was used as the attractant for male S. frugiperda; virgin beet armyworm females were used to attract male S. exigua moths. The electric grid trap captured more moths of both species than any of the other traps tested. Sticky traps were useful as long as their capacity was not exceeded. Color appeared to have little effect on the number of males of either species captured in the traps. Hourly sampling of the catches of S. exigua moths in electrocutor grid traps showed that these moths were most active 6–8 h after sunset.