Control of Grape Cane Gallmaker in Pennsylvania, 1976

Six insecticides were evaluated for control of grape cane gallmaker in 1976 on grapes near Harborcreek, PA. Plots consisted of 6 vines in a row replicated 3 times in a randomized block design. Guard plants of 3 vines within rows and one row between treated rows isolated the plots. Sprays were applied using an Ortho Spray-Ette Queen Size garden sprayer. This was operated off a high pressure hose on a Myers 61256ET2 hydraulic sprayer. Operating pressure was 100 psi. Sprays were applied to run-off, resulting in 100 gallons of solution being applied per acre. Spray application dates were May 27 and June 9; shoot lengths (± SD) at times of application were 10.4 inches (+ 2.2) and 26.6 inches (± 4.7), respectively. In sampling, 75 shoots were selected at random per plot and examined for gallmaker injury. Numbers of injured shoots were transformed t o ^ x + 0.5 and treated by analysis of variance and Duncan's modified (Bayesian) least significant difference test. Two fungicide applications (July 13 and August 16) were applied to the entire experimental area: Folpet 50WP 2 lb ai/acre.