During the summers of 1974 and 1975 an extensive mosquito control program was conducted near Laramie, Wyoming. Part of this work included aerial control of adult Aedes, primarily A. dorsalis and A. melanimon over irrigated pastures southwest and northwest of Laramie. It was concluded that adulticiding efforts of both years stopped an influx of adult Aedes into Laramie. In 1974 this influx was delayed for 26 days from the southwest and 14 days from the northwest. In 1975 the influx was delayed for 14 days from both the southwest and northwest. The results indicate that near Laramie, adult Aedes move approximately 5 mi. in a period of 14 to 26 days.