Apple, Tufted Apple Bud Moth Control Tactics, 1995
Authors: Hull Larry A. 
Published: December 2017

Various experimental and registered treatments were applied to replicated 12-15 tree plots in a randomized block design primarily to evaluate their activity against the tufted apple bud moth. Each treatment was replicated 4 times. Each plot consisted of alternating trees of ‘Yorking’, and ‘Golden Delicious’. These trees were planted to a spacing of 18 X 25 ft and were 16 yr old. The center ‘Golden Delicious’ and ‘Yorking’ trees in each plot were used as the primary sampling trees. Experimental sprays were applied with a Friend Airmaster ‘309’ calibrated to deliver 100 gpa at 2.4 mph. Applications timings were based on the accumulation of degree days from first adult moth capture in a sex pheromone trap (12 May) in order to predict various percentages of egg hatch for each brood of TABM. Degree day calculations were based on minimum and maximum developmental thresholds of 45°F and 91°F, respectively. Refer to the first table for a listing of application dates and degree day accumulations. All applications were complete sprays, except for one of the RH-5992 and RH-2485 treatments. These treatments were applied using the alternate row middle (ARM) system of spraying. A routine schedule of fungicides (Benlate 50DF, Penncozeb 75DF, Nova 40WP, and Ziram 76WP) was maintained throughout the experiment. One alternate row middle application of Swat 8E at 0.6 lb Al/acre (expressed as amount/acre for a complete spray) for control of the spirea aphid was made on 29 Jun. The effect of the sprays on WALH was evaluated by counting the number of nymphs/25 injured leaves/tree (cv. Yorking). Effectiveness of the treatments on SA was evaluated by counting the number of aphid-infested leaves/ 10 side terminals, and the number of aphids/most infested leaf (cv. Yorking). Effectiveness of the test chemicals on the ERM, TSSM and AF was evaluated by counting the mites several times during the season on samples of 25 random leaves/tree (cv. Yorking), 100 leaves/treatment. The effect of sprays on the predator S. punctum was evaluated by 3-min counts of adults and larvae around the periphery of the same trees. STLM was evaluated by a 5-min count of tissue-feeding mines around the periphery of the trees at the end of each generation. On 5 Jun, only spur leaves were examined, and on 24 Jul and 1 Sep only shoot leaves were examined for tissue-feeding mines (cv. Yorking). Shelters of the various leafrollers were counted in a 5-min examination of each plot tree on 20 Jul (cv. Yorking). All larvae were collected and returned to the laboratory for identification. Effectiveness of the treatments on fruit feeders on ‘Golden Delicious’ was assessed by scoring for injury a harvest sample of 100 fruit per tree from each of two center trees per replicate on 20 Sep and upto 25 dropped fruit per tree. For ‘Yorking’, injury was assessed on 150 picked fruit per tree from the two center trees in each replicate and up to 25 dropped apples per tree. In addition, 50 picked fruit per tree from two outside ‘Yorking’ trees were evaluated for injury. Russet evaluations were made on ‘Golden Delicious’ fruits (30 per replicate) from two replicates. Each apple was rated as 0 (no russet), 1 (raised lenticels), 2 (1-10% russeted surface), 3 (11-25% russeted surface), 4 (26-50% russeted surface), or 5 (&gt;51% russeted surface). Individual ratings were added to calculate a russet rating for each replicate. Possible ranges for the replicate russet ratings (and estimate of range of % of surface russeted) are 0-30 (none to raised lenticels), 31-60 (raised lenticels to 1-10% russeted surface), 61-90 (1-10% to 11-25% russeted surface, 91-120 (11-25% to 26-50% russeted surface), and 121-150 (26-50% to &gt;51% russeted surface). Both rates of Provado (0.50 and 0.075 lb Al/acre), Agri-Mek and Carzol provided excellent control of WALH at 4 and 13 days post-treatment with applications timed at petal fall. Provado at 0.075 lb Al/acre demonstrated the best control of SA followed closely by the high rate of Aphistar (0.25 lb Al/acre). There was a rate response with Aphistar against SA. Seasonal STLM control was obtained with single application of Agri-Mek at petal fall. Also showing excellent control of STLM were treatments of Provado and RH-2485. The single application of Agri-Mek at petal fall maintained seasonal control of ERM. The treatment of Vydate at the pink stage and Carzol at petal fall also provided good early season control, but ERM populations exploded at the end of Jul. Stethorus populations were high across all treatments except the Agri-Mek treatment at petal fall. Leaf shelters containing live TABM larvae were low across all treatments. Surprisingly, only the complete spray of RH-5992, the Penncap M only treatment applied for first brood TABM control, and the one treatment of Compound Z contained relatively high TABM larval populations. Fruit injury from other leafroller species was low and variable during 1995. The complete spray and ARM applications of RH-2485 showed the best control of other leafrollers. All treatments except Dipel 2X reduced fruit injury from first brood TABM below the control. Second brood TABM fruit injury was quite high across all treatments. RH-2485 applied both as complete and alternate row middle applications had the fewest number of fruit injured by second brood TABM. Also showing excellent activity against the second brood were the treatments of RH-5992, Dipel 2X, Xentari, Compound Z and the standard treatment of Penncap plus Lannate. Only the treatment of Penncap alone failed to show a difference from the untreated control. For overall percent clean fruit, all treatments except Penncap M alone were significantly different from the control. No russeting problems were observed. Pest pressure was moderate to high throughout the season depending upon species.