Abstract
Three methods for estimating the field developmental time of the southern pine beetle were compared. The estimates by each of the 3 methods were found to agree at high temperatures. Depending on the season of the year and temperature extremes, Method I (1st appearance of a stage to the 1st appearance of the succeeding stage) over- or under-estimated the developmental time estimated by Method IT (date 50% of the population was observed in a stage to date 50% of the population was observed in the succeeding stage) and Method III (points where highest densities were observed in succeeding stages). The egg stage was found to last 8-27 days, the larval stage 10-62 days, and the pupal stage 7-26 days, depending upon mean temperature. The range of temperatures observed in the field was between 4° and 28°C.