Apple, Insect Control, Hudson Valley, Highland, New York, 1983

Abstract

Abstract Treatments were applied to plots of eight trees, each a different cultivar. Plots were replicated three timas in a randomized complete block design. Most treatments were applied at pink, 2 May, petal fall, 22, 23 May, and in six cover sprays, 6, 21 Jun., 6, 21 Jul., 3 Aug., and 17 Aug. Advantage was applied with 2% oil on 12 Apr. and by itself in cover sprays directed at San Jose Scale crawlers on 21 Jun., 6 Jul., 3 Aug., and 17 Aug., Imidan was applied on the other dates. Larvin 3.2F was applied at 10.0 and 20.0 oz form./lOO gal as the 4th and 5th treatments at pink, 2 May, while all Larvin treatments were omitted from the 21 Jul. cover spray. Bay Sir 8514 was applied at pink, 2 May and again on 21 Jun and 6 Jul., Guthion being used on the remaining dates. FMC 54800 and FCR 1272 were applied in the 2 May pink spray. Orthene was only applied 2 May, 23 May, and 6 Jun., Guthion being used on the remaining dates. Imidan, FMC 54800, and Larvin were all applied 22 May, and again on 23 May, following a rainstorm the night of the 22nd. Treatments were all applied dialute to runoff by high-pressure handgun sprayer at 400 lb/in2 delivering 4.2 gal spray/tree (403 gal/acre) except for the final two applications using 5.2 gal spray/tree (500 gal/acre). Trees were 19-yr-old, 12 ft high, on the EM2 rootstock, and spaced 15 by 30 ft. Plictran 50WP, 4 to 6 oz/100 gal was the primary miticide used, although Carzol 92SP 6 oz (AD/100 gal was applied to FCR 1272 and Penncap + Pydrin plots on 3 Aug. while Kelthane 4F 1 pt (AD/100 gal was applied to Larvin plots on the same date. Fungicide applications over all plots include: Bravo 500 3 qt (AD/100 gal, 12 Apr.; Vangard 10WP 2 oz/100 gal, 10, 17 Jun., and 13 Jul.; Captan 50WP 0.4 lb (AD/100 gal, 10 and 17 Jun.; and Polyram 80WP 1.13 lb(AD/100 gal, 13 Jul. All trees wee thinned with 10 ppm naphthaleneacitic acid on 2 Jun. April and May were unusually cold and wet, while July and August were much hotter and dryer than normal. Insect population densities were normal throughout the season. Insect damage was assessed at harvest by examining 100 fruit/cultivar per plot from ‘McIntosh’ 7 Sep., ‘Cortland’ 23 Sep., ‘Golden Delicious’ 3 Oct., and ‘Red Delicious’ 10 Oct.