I spoke to Rick Brandenburg and Dominic Reisig about how quickly to expect acephate (Orthene) to kill thrips. Within 24 hours, many of the immature thrips will be controlled (dead). However, there will not be complete control. There will always be some survivors. In the vast majority of fields right now, the survivors are not resistant to acephate - it's just close to impossible to kill all of the individuals. There are always some escapes.