Apple, Codling Moth Control with Insecticidal Oil and Guthion, 1995

Four highly refined insecticidal oils, Orchex 796 98%, Orchex 692 98%, WS-2928 98%, and Guthion were evaluated for their ability to control CM over the entire season. The test was conducted in an apple orchard at the Tree Fruit Research and Extension Center. The trees were 15-yr-old spur type Delicious on dwarfing roots. Treatments were applied to 1-tree plots replicated 5 times in a randomized complete block. All treatments were applied with a handgun sprayer at 300 psi to the point of drip. The CM injury evaluations were made on 6 Jun following the first generation, and at harvest on 31 Aug. Twenty-five apples per replicate were sampled on 6 Jun and the total number of CM injured fruit and those marked by spray residue recorded. At harvest, all fruit from each replicate were examined and the number of CM and PLR injured fruit recorded. Because of the high percentage of CM injured fruit at harvest, a 10-fruit subsample was chosen at random from each replicate and the number of CM stings and entries per fruit recorded. PLR and WALH were sampled on 8 Aug. Twenty shoots were examined and the total number of active PLR larval feeding sites recorded. Ten leaves were examined for the presence of WALH and the total number of nymphs recorded.