Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Effectiveness of superior oil applied to apple for control of the San Jose scale, Quadraspidiotus perniciosus, and the European fruit scale, Quadraspidiotus ostreaeformis (Homoptera: Diaspididae).

Abstract

Annual applications of superior oil reduced populations of Quadraspidiotus perniciosus and Q. ostreaeformis on apple trees in Ontario and reduced fruit infestation in the last 2 years of a 3-year study. However, the proportion of fruit infested with scales was not substantially reduced after 3 successive years of oil application. More fruit from the top portion of treated trees was infested than from the lower portions, indicating that spray application was not evenly distributed or that motile stages of the scales moved selectively to the upper portions of the trees.