Abstract 122 photographs gathered by Knowlton during his work as an entomologist at Utah State University. The majority of these photos show different types of equipment including microscopes, sprayers, mixers, and dusters. Other photos show specific pest control projects including cricket control from 1937-1941 and fly control on dairy cows. folders fifteen through nineteen are an interesting contrast to the rest of the collection showing research done to determine the deaths of numerous honey bees....