Apple Pandemis Control, Pink Application, 1984

Abstract

Abstract Insecticide treatments were evaluated for control of overwintered apple pandemis larvae in a 5-year-old orchard on a semi-dwarf rootstock located at the Tree Fruit Research Center. Treatments were applied with a handgun sprayer at 400 psi to the point of drip simulating a dilute spray of approximately 400 gal per acre. The experimental design was a randomized complete block with 4 single-tree replicates per treatment. Treatments were applied at pink stage of flower bud development on 17 Apr. Temperature at time of application was 50°F with a light breeze (<2 mph). No pretreatment counts were taken through a general inspection indicated that a high leafroller population was present (about 10% fruit buds infested). Posttreatment evaluation was made on 26 Apr when most king bloom had opened. All flower clusters on each tree were examined. The total number of flower clusters, clusters with feeding injury and clusters with live larvae were recorded. Mites were sampled on 11 Jul and 16 Aug. A 25-leaf sample was collected from each tree, returned to the laboratory, brushed, and number of mites counted. Data are presented as mean mites per leaf for the season.