Apple, Insect Control, 1975-1976

Dimilin (25% WP) was evaluated over 2 seasons in a 16 year-old dwarf apple planting. The 1975 experiment consisted of one replicate of 40 Red Delicious, Golden Delicious and Jonathan trees, treated on 5-5, 5-29, 6-6, 6-19, 6-26, 7-15, 7-29 and 8-12. The 1976 experiment consisted of 2 replicates of 6 Jonathan trees each treated on 4-29, 5-10, 5-18, 6-3, 6-7, 6-21, 7-6, 7-21, 8-3, and 8-18. Applications were made with a John Bean sprayer operated at 400-450 psi at the rate of 5 gal/tree. There was considerable rainfall in May and June 1976, necessitating an additional application. Above normal temperatures during April 1976 caused an abnormally early bloom. Fruit infestation ratings were obtained by picking fruit at random and examining for damage Under heavy codling moth pressure, Dimilin performed well at fairly low dosages both seasons. No control was obtained against leafrollers and plum curculio at these dosages.