Table 3. Season-long apple maggot fly (AMF) injury and trap captures in two types of 

 full second-level IPM blocks, in transitional second-level IPM blocks, and in first-level 

 IPM blocks. 1 



J Means in each couplet in each column followed by a different letter are significantly 



different at odds of 19:1. 



^hese traps were positioned two rows inside the perimeter. 



full second-level IPM (test) blocks (Table 1). In 

 both types of blocks, tarnished plant bugs 

 caused the greatest amount of injury, followed 

 by plum curculio, European apple sawfly, and 

 green fruitworm. Pesticide use against early 

 season fruit pests was very similar in second- 

 level and first-level blocks, probably because 

 most growers based their treatment of first-level 

 IPM blocks on monitoring (Table 2). 



Summer Fruit-injuring Pests. Odor- 

 baited sticky red spheres were hung every 5 

 yards on perimeter apple trees of each experi- 

 mental block to intercept immigrating apple 

 maggot flies (AMF). In three of the blocks, these 

 were baited with butyl hexanoate, a synthetic 

 fruit odor. In the other three blocks, traps were 

 baited with both butyl hexanoate and ammo- 

 nium carbonate, a synthetic food odor. 



Interception trap captures averaged 2936 



per block in the three full second-level blocks 

 where synthetic fruit odor alone was used, indi- 

 cating high AMF pressure (Table 3). Captures 

 of AMF on four interior unbaited red spheres 

 (indicative of AMF penetration into the block 

 interior) averaged 34% more in second-level 

 blocks baited with fruit odor alone than in 

 nearby first-level blocks. AMF injury in these 

 second- level blocks was also slightly higher than 

 in nearby first-level blocks (0.6% vs. 0.1%). In 

 one of the three second-level blocks baited with 

 butyl hexanoate alone, interior monitoring trap 

 captures in early August suggested sufficient 

 AMF penetration to warrant pesticide treat- 

 ment. Hence, Guthion™ was applied on August 

 6. 



In the three full second-level blocks baited 

 with butyl hexanoate and ammonium carbon- 

 ate, interception trap captures averaged 3562 

 per block, again indicating high AMF pressure. 



Fruit Notes, Spring, 1992 



