Mague, D.L., & Reissig, W.H. 1983a The phenology of the San Jose scale (Homoptera: Diaspididae) in New York State apple orchards.. Canadian Entomologist 115: 717-722.
Notes: Quadraspidiotus perniciosus; pheromone trapping; reports two periods of male flight activity; shows logistic relationship between crawler density and fruit infestation.