To determine whether aerosolization could impair bacterial survival, Pseudomonas syringae and Erwinia herbicola were aerosolized in a greenhouse, the aerosol was sampled at various distances from the site of release by using all-glass impingers, and bacterial survival was followed in the impingers for 6 h. Bacterial survival subsequent to aerosolization of P. syringae and E. herbicola was not impaired 1 m from the site of release. P. syringae aerosolized at 3 to 15 m from the site of release at a temperature of 12 deg C and a relative humidity of 80% survived 35- to 65-fold better than P. syringae released at 27 deg C and a relative humidity of 40%. No difference was observed in the survival of P. syringae and E. herbicola following aerosolization at the same temperature and relative humidity. Bacteria sprayed directly onto bean and oat plants established stable populations at comparable numbers on both plants over an 8-day period following inoculation. Bacteria that inoculated adjacent plants by drifting downwind up to 5 m were detectable at an initial population of 100 CFU/g on oats and 100,000 CFU/g on beans 2 h after the spray. However, bacterial populations on both plants were undetectable within 48 h. (Copyright (c) 1990, American Society for Microbiology.)