an increase, a decrease, or no change in pest incidence 

 across the 8 years of study. 



For codling moth, injury across the 8 years 

 averaged 0.3% in test blocks vs. 0. 1 % in check blocks 

 (not a significant difference). The slope of the 

 regression line indicated a slight, nonsignificant 

 tendency toward an increase in injury by codling moth 

 in test blocks across years, but no such tendency in 

 check blocks. 



For lesser appleworm, injury across the 8 years 

 averaged 1 .4% in test blocks vs. 0.2% in check blocks 

 (not a significant difference). As with codling moth, 

 the slope of the regression line indicated a slight, 

 nonsignificant tendency toward an increase in injury 

 by lesser appleworm in test blocks across years but no 

 such tendency in check blocks. 



For leafrollers (combined obliquebanded and 

 redbanded), injury across the 8 years averaged 1.3% 

 in test blocks vs. 0.5% in check blocks (not a significant 

 difference). The slope of the regression line indicated 

 a moderate and significant tendency toward an increase 

 in injury by leafrollers in test blocks across years 

 compared with only a very slight, nonsignificant 

 tendency toward an increase in injury in check blocks 

 across years. 



increase in injury of lepidopteran pests to apples across 

 years in check blocks to which two or three insecticide 

 sprays were applied in July and August. In test blocks 

 that received traps to control apple maggot but no 

 insecticide after mid-June, injury to fruit by codling 

 moth and lesser appleworm tended to increase slightly 

 but nonsignificantly across years compared with a more 

 substantial and significant tendency toward increased 

 injury by leafrollers across years. 



These findings demonstrate the value of long-term 

 studies and suggest that among lepidopteran pests of 

 apples in Massachusetts, leafrollers are the most likely, 

 over several successive years, to cause increasing 

 damage to fruit in the absence of insecticide sprays 

 after mid-June. Fortunately, new materials such as 

 spinosad and tefubenozide are comparatively safe 

 insecticides that can effectively control leafrollers 

 while inflicting relatively little harm on beneficials. 

 Apple growers who practice advanced-level IPM 

 should pay close attention to possible buildup of 

 leafrollers in the absence of summer organophosphate 

 insecticide sprays and control leafrollers with 

 alternative measures. 



A ckn o wledgem en ts 



Conclusion 



Findings showed no increase or only a very slight 



This work was supported by State/Federal IPM 

 funds and the Massachusetts Society for Promoting 

 Agriculture, to which we are most grateful. 



*%JU %1^ %3^ %3^ 

 #1^ ^j^ ^1^ ^1^ 



Fruit Notes, Volume 66, 2001 



13 



