Apple, Insect Control, Hudson Valley, Highland, New York, 1979

Eight-tree plots of from 5 to 7 different apple cultivars were replicated 3 times in a randomized complete block design. The trees were 15 years old on the EM2 rootstock and spaced 15 × 30 ft. Treatments were applied atpetal fall, May 15, and in 6 cover sprays, May 29, Jun 14, 28, Jul 12, 26, and Aug 13, except the UC 55248 treatment which was applied at tight cluster, Apr 23, and again on Jul 12. Treatments were applied dilute to run-off using a high pressure handgun sprayer at 400 psi delivering 4.2 gal spray/tree or 403 gal/acre. Additional sprays applied over the entire block included Difolatan 4F 5 gal/acre, April 19; Cyprex 65W 2lb/acre, Jun 1; and Plictran 50W 4 oz/100 with the Jul 12 treatments. Above normal temperatures and below normal rainfall occurred during the month of Jul, while more normal conditions prevailed during the rest of the season. Insect pressure was below normal for most species evaluated.