fruit sampled at harvest in these 6 blocks from 1987 

 through 1989, none were injured by codling moth 

 [Fruit Notes 55(l):4-9]. These findings were quite 

 encouraging. We then asked ourselves whether 50 

 yards rather than 100 yards free of codling moth host 

 trees might provide sufficient barrier to preclude im- 

 migration of second-generation females. 



In 1990, we evaluated codling moth injury in 6 

 commercial apple blocks (2 to 3 acres each) where 

 abandoned apple and pear trees had been removed 

 in 1988 at different distances from the block perime- 

 ter. All 6 blocks received 3 to 4 insecticide sprays 

 against plum curculio and other pests from April to 

 early June but no insecticide thereafter. 



The results (Table 1) show that in 2 blocks where 

 no apple or pear trees had been removed from the 

 surrounding habitat, codling moth injury to fruit at 

 harvest averaged 15% on abandoned trees within 

 to 50 yards of the block and 0.44% on commercial 

 trees within the block. In 2 blocks where all unman- 

 aged apple and pear trees had been removed within 

 50 yards of the block, injury averaged 16% on aban- 

 doned trees within 50 to 100 yards of the block but 0% 



Table 1. Codling moth injury (%) to fruit at harvest in (a) abandoned apple 

 trees, (b) commercial blocks that did not receive any insecticide after early 

 June, and (c) commercial blocks that received 2 to 3 applications of insecticide 

 against apple fly maggot in July and August, 1990. 



on commercial trees within the block. Likewise, 

 there was no codling moth injury to commercial fruit 

 in blocks where all unmanaged apple and pear trees 

 within 100 yards of the block had been removed. In 

 blocks adjacent to each of these 6 test blocks, there 

 was no codling moth injury under conditions where 

 2 to 3 insecticide sprays had been applied against 

 apple maggot in July and August. 



In conclusion, our findings from 1987 through 

 1990 show clearly that second-generation codling 

 moths can be controlled successfully in Massachu- 

 setts orchards by the habitat management tech- 

 nique of removing all abandoned apple and pear 

 trees within 100 yards of the orchard perimeter. Our 

 findings in 1990 suggest that abandoned host tree 

 removal within 50 yards of the perimeter may be just 

 as effective as within 100 yards, but that allowing 

 abandoned fruit trees to persist within 50 yards of 

 the perimeter is not effective. Success of this cul- 

 tural approach to managementof second-generation 

 codling moths depends on controlling the first gen- 

 eration in May and early June through pesticide 

 sprays applied primarily against plum curculio and 



on picking up drops 

 after harvest to pre- 

 vent within-orchard 

 population buildup. 



Distance between abandoned 

 and commercial blocks (yards) 



Treatment 



0-50 



50-100 



100+ 



Abandoned trees 



Commercial trees 

 receiving no insecticide 

 after early June*** 



Commercial trees receiving 

 2-3 insecticides after 

 early June*** 



14.7* 



0.4 



0.0 



16.4* 



0.0 



0.0 



0.0 



0.0 



*Samples from 5 trees to 50 yards from orchard, 44 fruit per tree. 

 **Sample from 3 trees 50 to 100 yards from orchard, 21 fruit per tree. 



*** 



Sample from 10 trees per block, 80 to 90 fruit per tree. 



We thank the 

 Northeast Regional 

 Project in Integrated 

 Management of 

 Apple Pests (NE 156) 

 and the Northeast 

 Regional Low-Input 

 Sustainable Agricul- 

 tural Project for sup- 

 porting this work. 

 Our thanks also to 

 the participating 

 growers: BillBroder- 

 ick, Dave Cheney, 

 Wayne and Jesse 

 Rice, Tony Rossi, 

 Steve Smedberg, and 

 Maurice Tougas. 



Prom: Thomai, J.J. 1906. The American Fruit 

 Culturist. Orange Judd Company, New York. 



Fruit Notes, Winter, 1991 



17 



