Abstract
Improvements in the rearing methods for axenic mountain pine beetles were made by standardizing the nutritional and physical composition of a yeast-fortified ground phloem diet. By eliminating handling and possible malnutrition of neonate larvae, and by use of individual rearing units to reduce hazards associated with microbial contamination, one person produced batches of 400–500 axenic beetles. Beetles produced by this method were morphologically and anatomically equivalent to and more fecund than field beetles, were significantly smaller than their parental stocks, and perhaps required more degree hours above 40 °C in developing from egg to adult.