Efficay of a Systemic Insecticide in Reducing Populations of Black Pineleaf Scale (Nuculaspis Californica)    (View PDF)

Paul T. Flanagan

Abstract: In 2001, 66 ponderosa pines (Pinus ponderosa) infested with black pineleaf scale (Nuculaspis californica) near Leavenworth, Washington, U.S., were selected for an insecticide trial. Twenty-two pines were injected with a systemic insecticide in October 2001; in March 2002, an additional 22 pines were similarly injected. The remaining 22 pines served as a control. Branches were collected in October 2002, and scale density per meter of foliage was compared among the fall treatment, spring treatment, and control trees. Both spring and fall treatments significantly reduced scale densities on 2002 and 2001 foliage. The spring treatment was more effective than the fall treatment.

Keywords: Ponderosa pine; black pineleaf scale; systemic insecticide; plant health; IPM; acephate.

https://doi.org/10.48044/jauf.2003.036