Apple, Concentrate Airblast Insecticide Test, 1986

Experimental sprays were applied to 3 tree plots in a randomized block design consisting of 2 replicates of York Imperial and 2 replicates of Golden Delicious. Sprays were applied with a Myers Mity Mist sprayer at 25 gal/acre/alternate side at 2 mph. Rates for treatments are listed as amounts/acre/both sides spray. Spray dates for the alternate side treatments were, 9, 17 and 27 May; 4, 12, 19 and 26 Jun; 7, 16, 23 and 30 Jul; 8, 15 and 25 Aug; 6 Sep. Lorsban 50WP (1361 g/acre) was substituted for the first 2 Danitol treatments and the Spur treatment on 27 May, 4 Jun (first Danitol treatment only), 12 Jun (first Danitol treatment only), 7, 16, 23 and 30 Jul; 25 Aug (2 Danitol treatments only); 6 Sep (2 Danitol treatments only). Kelthane 4F (1.89 liters/acre) was applied as a complete spray to the Larvin, TD-2207, Lorsban and control treatments on 30 Jul. Effectiveness on AA was evaluated by counting aphid-infested leaves/20 terminals. The effect of sprays on WALH was evaluated by counting nymphs/ 25 leaves/tree. Effectiveness of test chemicals on ERM was evaluated by counting mites several times during the season on samples of 25 leaves/tree, 100 leaves/treatment. The effect of sprays on the predator S. punctum was evaluated by 3-minute counts of adults and larvae around the periphery of test trees. Effectiveness of chemicals on fruit feeders was assessed by scoring for injury all drops after 1 Jul and a picked sample on 23 Sep. Apple samples averaged 170 fruits/replicate and 680/treatment. Pest pressure was heavy throughout the season. Russet ratings are based on 30 Golden Delicious apples/replicate, 60/ treatment. Fruits were rated as 1 (no russeting), 2 (light russeting), 3 (moderate russeting), or 4 (severe russeting). Possible ranges were 30-60 (none to light), 60-90 (light to moderate) 90-120 (moderate to severe).