Timing of Confirm Applications for Codling Moth Control, 1995

Abstract

Abstract The study was conducted on mature ‘Bartlett’ pear trees in a commercial orchard near Fairfield, Calif. Five treatments were replicated four times in a RCB design. Each replicate consisted of an individual tree. Three Confirm application timings (100, 200 and 300 degree days (DD)) were applied after the beginning of each CM flight and were compared to Guthion at 200 DD and an untreated control. DD were calculated with a 2 Apr biofix for the first generation and 25 Jun biofix for the second generation using a single sine horizontal cutoff model with a lower threshold of 50° F and upper threshold of 88° F and with air temperature from the IMPACT weather station in Cordelia. Treatments were applied with a handgun orchard sprayer operating at 200 psi and delivering 400 gal/acre of finished spray (3.85 gal/tree). Control of the first CM generation was evaluated on 13 Jun by inspecting 50 fruit from the bottom of the tree canopy and 50 fruit from the top of the tree canopy per replicate. Control of the second CM generation was evaluated at commercial harvest on 24 Jul by inspecting 125 fruit from the bottom of the tree canopy and 125 fruit from the top of the tree canopy per replicate.