Apple, Grape Mealybug Control, 1991

Mature apple trees were sprayed with a Metters airblast sprayer traveling 1.5 mph, with flip-over nozzles calibrated to apply 80 and 400 gal per acre. Plots consisted of 6 unreplicated half-acre blocks, with four trees chosen as subsamples from each plot. Trees were heavily infested with early instar GMB crawlers which had settled at the leaf petioles on vigorous shoots. Application was made 19 Jul and was evaluated 22 Jul. Treatments were evaluated for GMB control by counting nymphs dead and alive at the first 6 petioles (below the first fully unfurled leaf) on 4 shoots per subsampled tree (16 per treatment). Percent mortality was calculated.