Data in Table 2 reveal the average amount of fruit 

 injury caused by all insect pests active after mid-June. 

 Over the 3 years, apple maggot injury decreased from 

 1.4 to 0.5 to 0.3% in the second-stage blocks. The 

 average of 0.4% maggot injury over 1988 and 1989 in 

 these blocks was comparable with the average of 0.2% 

 maggot injury in the first-stage IPM blocks. These data 

 show that the interception trap approach is very little 

 different from insecticide sprays in ability to provide a 

 commercially acceptable very high level of maggot- free 

 fruit (0.5% or less maggot injury). 



Codling Moth 



Data in Table 2 also show that the method of 

 removing all apple trees within 100 yards of the or- 

 chard perimeter was as effective as a standard first- 

 stage program in preventing codling moth injury to 

 fruit. Apparently, sprays against plum curculio in late 



May and early June pro- 

 vide excellent control of 

 any first-generation cod- 

 ling moth eggs that might 

 have been laid, while the 

 distance of 100 or more 

 yards from the orchard 

 perimeter is too great to 

 be overcome by potential 

 second-generation cod- 

 ling moth immigrants in 

 July and August. We are 

 initiating a field test to 

 determine whether re- 

 moving all apple trees 

 within 50 yards of the 

 orchard perimeter 



achieves the same high 



level of codling moth disruption as removing all apple 



trees within 100 yards. 



Leafrollers and Lesser Appleworm 



In our judgement, the greatest potential threat to 

 future success of second-stage IPM practices lies in 

 buildup of summer leafrollers and lesser appleworms. 

 These pests have begun to build up substantial toler- 

 ance to several types of insecticides in recent years in 

 New York and apparently also in a few Massachusetts 

 orchards. Hence, the problem of increasing fruit dam- 

 age from leafrollers and lesser appleworms seems to be 

 a general one in the Northeast. 



As shown in Table 2, in 1989 combined leafroller 

 and lesser appleworm damage in second-stage IPM 

 blocks averaged slightly greater than in first-stage 

 blocks (1.7 versus 1.1%). These pests have a much 

 broader host range and may be more mobile than 



Fruit Notes, Winter, 1990 



