Table 4. Fruit injury by codling moth (CM), leafroller (LR), and lesser 

 appleworm (LAW) in second-level and first-level IPM blocks in 1994.* 



Type of block 



CM 



LR 



LAW 



♦Means in each couplet in each column followed by a different letter are 

 significantly different at odds of 19:1. Two hundred fruit of each cultivar 

 present in each second-level block were sampled at harvest in both second- 

 level and first-level blocks. All blocks contained at least one of the following 

 cultivars, and some contained up to four of these: Mcintosh, Cortland, 

 Delicious, Empire, Golden Delicious. Average number of fruit sampled per 

 block = 500. When sampling a cultivar, we examined 10 fruit on each of 20 

 interior trees. An additional 10 fruit on each of 10 perimeter trees per 

 cultivar (when cultivar present on a perimeter row) were sampled for apple 

 maggot fly and codling moth. 



blocks. Again, this observation suggests that lepidopleran 

 pests may provide a special challenge in low-spray orchard 

 situations. 



LAW, a pest which first became a concern in 1993, was 

 a major concern in one second-level block in 1994. The 

 block had several rows of Cortlands bordered by a field of 

 young trees and shrubs, and migration from the field toward 

 the interior of the block seemed to have occurred. While the 

 average of LAW injury in second-level blocks was not 

 significantly higher than in first-level blocks, field observa- 

 tions suggested a direct link between low-spray manage- 

 ment and fruit injury. In addition, Cortlands seem far more 

 susceptible to LAW injury than Mcintosh, as Cortland and 

 Mcintosh fruit in the same location have shown very 

 different injury rates over the past two years. We plan to 

 conduct research on LAW beginning in the summer of 

 1995. 



No insecticide was applied against fruil-injuring pests 

 after mid-June in second-level blocks. Growers applied an 

 average of 1 .7 dosage equivalents of insecticide against fruit 

 pests after mid-June in first-level blocks, spraying such 

 blocks an average of 2.9 times (Table 1). 



Summer Fruit-injuring Pests: 

 Transitional Second-level IPM 



Every three weeks after early June, perimeter row apple 

 trees in transitional second-level blocks were treated with 



insecticide to control 

 AMF. The block interior 

 remained free of insecti- 

 cide directed toward fruit 

 pests after early June. 

 AMF injury was higher in 

 1994 than in previous 

 years of the pilot program, 

 but was comparable in the 

 second- and first-level 

 blocks (2.6 vs. 2.7%). 

 AMF captures on interior 

 unbaited monitoring traps 

 were similar in first- and 

 second-level blocks (7.4 

 vs. 8.9). 



Injury by CM, LR, and 

 LAW was lower than in 

 1993, and levels were only 

 slightly higher in second- 

 level than in first-level 

 blocks (Table 4). LR injury 

 decreased from 0.7% in 

 1993 to 0.1% in 1994. 

 Blocks in which LR had 

 been a problem in the past 

 may have benefited by ear- 

 lier than usual picking of fruit, particularly of Cortlands. 

 Field observations suggest that significant LR injury in our 

 experimental blocks has usually occurred within the last few 

 weeks before harvest. 



Total insecticide use after early June averaged 0.4 

 dosage equivalents in second-level blocks compared with 

 1 .6 dosage equivalents in first-level blocks (Table 1 ). Many 

 growers employed greater than usual pesticide spray events 

 in their first-level blocks, due mainly to high AMF numbers 

 and rainy weather. 



Foliar Pests and Beneficial Natural Enemies: 

 Full Second-level IPM 



Early season management of foliar pests relies on 

 monitoring and chemical intervention if initial pest popu- 

 lations are high. Two dormant oil applications were recom- 

 mended for control of overwintering ERM eggs. Five red 

 sticky rectangular traps were hung on tree trunks in each 

 block in mid-April to monitor for the emergence of overwin- 

 tering ABLM adults. Foliar sampling began in late April 

 and focused on ERM and WALH, as well as on the appear- 

 ance of ABLM eggs. If necessary, pesticide was recom- 

 mended to control early populations of any of these pests if 

 they existed at problem levels. 



Seasonal averages for pesl mite populations in 1994 

 were a bit lower than in 1993. Unlike 1993, most locations 



Fruit Notes, Winter, 1995 



