Apple, Handgun Trials of New Insecticides Against Oblr, 1996

Abstract

Abstract Treatments were applied with a truck-mounted, high pressure (450 psi), handgun sprayer dilute to run off to single apple tree plots in 2 orchards: ‘Idared’ trees (Brown orchard), which were about 15 years old, 13 ft high, and planted 19 X 27 ft apart, and ‘Rome’ trees (Nesbitt orchard), which were about 8 ft high and planted 11 X 18 ft apart. Treatments were arranged in a RCB design, separated by unsprayed buffer trees, and replicated twice in each orchard. All materials were applied on a 3-spray schedule, at 1st hatch (2 Jul), mid-hatch (16 Jul), and on 29 Jul. Check plots were not sprayed with insecticides during the test. Summer populations of larvae were compared by examining 20-50 growing terminals on each tree for live larvae on 9-11 Jul and again on 23-24 Jul. Fruit damage from the 1st summer generation of larvae was estimated initially on 1-2 Jul and again on 20-24 Aug by sampling up to 100 apples from each tree. At harvest (4 Oct for the ‘Rome’ applies in the Nesbit Orchard and 14-15 Oct for the ‘Idared’ applies in the Brown Orchard), up to 100 applies were sampled from each tree and OBLR damaged fruit was classified according to USDA grading standards into the categories of “Fancy”, #1, and culls.