Apple, Control of the Pandemis Leafroller in Summer with RH-5992, 1993

An experimental insecticide, RH-5992, was evaluated for its ability to control PLR larvae of the summer generation. The test was conducted in an apple orchard located near Wenatchee. Trees were 10-yr-old spur-type ‘Oregon Spur II’ on seedling roots. The orchard was irrigated by undertree sprinklers on a weekly 12-h set. Treatments were applied to three-tree plots replicated five times in a RCBD, with a handgun sprayer at 300 psi to the point of drip, simulating a dilute spray of approximately 400 gpa. Treatments were applied on 19 Jul at the beginning of the egg hatch period. The post-treatment evaluation was made on 5 Aug when surviving larvae could be easily located in growing shoots. Each tree was sampled and the number of live leafroller larvae recorded.