Angerilli, N.P.D., & Logan, D.M. 1986 The use of pheromone and barrier traps to monitor San Jose scale (Homoptera: Diaspididae) phenology in the Okanagan Valley of British Columbia.. Canadian Entomologist 118: 767-774.

Notes: Comparisons of three isomers of Quadraspidiotus perniciosus pheromone; pheromone baited traps were compared with sticky barrier traps for the detection and monitoring of male emergence activity; each trap produced a different activity pattern relative to both calendar days and accumulated degree-days; suggestion of a trend towards decreasing degree-day requirements as the insect's distribution moves north.