Table 3. Season-long apple maggot lly (AMF) injury and trap captures in second-level IPM blocks and 

 first-level IPM blocks in 1994. * 



*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 followmg 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 (when cultivar present on a perimeter 

 row) were sampled for apple maggot fly and codling moth. 



a synthetic food odor released through a small puncture in 

 a foil wrapped package. Traps were cleaned every other 

 week to maintain high capturing power. 



Trap captures were up drastically from 1993 (and all 

 previous years), with interception trap captures averaging 

 12,588 flies per full second-level block, as compared to 

 5023 in 1993. It should be noted, however, that approxi- 

 mately 60% of all AMF captured on perimeter traps in 1 994 

 were captured in one orchard. Although the difference was 

 not statistically significant, AMF captures on four interior 

 unbaited monitoring traps were almost twice the number 

 captured in nearby first-level blocks (Table 3). AMF injury 

 in second-level blocks at harvest was considerably greater 

 than in 1993, but was not significantly different from injury 

 levels in first-level blocks (4.2 vs. 3.0%). While the higher 

 interior trap captures were a concern, the relatively similar 

 injury levels suggest the perimeter traps maintained a level 

 of control fairly comparable to first-level blocks. Better trap 

 positioning and an improved delivery system for food odor 

 bait, as well as movement of the interception traps to later 

 cultivars as earlier cultivars were harvested, may have aided 

 the effectiveness of the trapping program. 



While AMF injury levels among fruit on the trees at 

 harvest were not a major concern, AMF levels in drops in 

 several orchards were cause for concern. Some cultivars, 

 especially Jersey Mac and Golden Delicious, had up to 50% 



AMF infestation in dropped fruit at harvest. It has been our 

 policy to recommend immediate removal of drops after 

 harvest, a policy that is difficult if not impossible to imple- 

 ment on many farms, given labor and time constraints. 

 Research being conducted by a graduate student in our 

 program suggests that even if all drops were to be removed 

 immediately after harvest, such removal would have al- 

 lowed considerable AMF larval emergence to have occurred 

 before drop removal, because AMF larvae often leave fruit 

 soon after it drops. It appears that cultivars susceptible to 

 AMF could lead to infested drops and could cause difficul- 

 ties in a second-level IPM management program by allow- 

 ing within-orchard buildup of AMF. 



Fruit injury by CM and LR was higher in second-level 

 than in first-level blocks, and was higher in 1994 than in 

 1993 (Table 4). CM was considerably more evident in 1994 

 than in 1991-1993 and was a problem in a number of more 

 traditionally-managed blocks across Massachusetts, as well 

 as in second-level blocks. We feel that removal of aban- 

 doned host trees from within 100 yards of a second-level 

 block provides good control of CM in average years. In 

 years when CM are forced to travel farther distances due to 

 limited wild host resources (as in 1994), however, tree 

 removal may not be sufficient to protect a low-spray block. 

 LR injury, while not much higher than 1993 levels, was 

 significantly greater in second-level than in first level 



Fruit Notes, Winter, 1 995 



