The daily and seasonal emergence patterns of Synanthedon pictipes (Grote and Robinson) were determined under field conditions in Door County, Wisc., m 1972 and 1973. Daily emergence occurred during the morning hours at times related to temperature conditions. The earliest emergence was recorded at 5:45 AM. No emergence took place at temperatures below 15°C,. but on fast warming days emergence was not initiated until the temperature was much higher. It is suggested that a certain number of thermal units accumulation followmg sunrise are required for emergence to take place. The observed seasonal emergence extended between 6 June and the week ending 3 August. The ratio of males:total number of adults declined significantly on both daily and seasonal scales.