The importance of placement of microbial insecticides so that they may be ingested or come in contact with the target pest species is well recognized. On field crops attempts to accomplish this goal have been with application systems developed for contact chemical pesticides. Dusts, high volume foliar applications, and ultralow volume applications generally provide more uniform plant coverage than low volume applications and microbial insecticides thusly applied appear more effective against exposed foliage feeders. Granular and sprayable baits and foliar sprays with large droplet sizes have been more effective against certain concealed feeders than low volume application.