Pine Needle Scale Control on Scotch Pine in Centre CO., PA, 1986

Five insecticides were evaluated to control the summer generation crawlers of the pine needle scale on heavily infested 5-6 ft scotch pine Christmas trees. Foliar sprays were applied to the point of run-off with a Solo 425 backpack hand-pump sprayer. Each treatment was applied to 4 single tree replicates. Treatments were made on 17 Jul. The air temp was 68°F and the % RH was 86. Rainfall occurred within 24 hr following completion of all treatments. One week posttreatment (24 Jul), a minimum of 5 infested needle fascicles were randomly removed from each tree. Fascicles were then individually placed in plastic bags and transported in an ice cooler back to the laboratory where the viability of the first 100 nymphs observed under a stereo-dissecting microscope was determined. Counts were always made from a minimum of 5 fascicles.