A laboratory study was conducted to determine the range of temperatures and humidities at which conidial sporulation and germination ofEntomophthora gammae(Weiser) would occur. The fungus was able to sporulate at relative humidities of 80–100% and was inactivated by humidities of 50% and below. Conidia germinated at 98 and 100%RHand could not survive exposure to humidities below 75%RH.E. gammaesporulated and germinated at 10–26.7°C but could not survive prolonged exposure to 32.2 and 37.8°C. When cadavers were frozen, the pathogen was inactivated in less than 1 h.