areas of greatest darkness within an orchard 

 (that is, toward tree trunks). Placement of 

 black pyramid traps next to tree trunks 

 capitalizes on this behavioral tendency, which 

 is expressed just as strongly in an understory of 

 vegetation as on bare ground. 



Even at this most favored tree-trunk 

 position, however, unbaited black p5Tamid 

 traps fall well short of being an effective means 

 of monitoring the occurrence of curculio injury 

 to apples. Additional studies (see following 

 article) indicate that a principal cause for the 

 failure of captures by unbaited pyramid traps 

 on ground to be good predictors of fruit injury in 

 tree canopies lies in the means by which 

 curculios approach pjrramid traps and ap- 

 proach tree canopies: by crawling or by flight. 

 Evidence suggests that during warm weather, 

 curculios may enter tree canopies directly by 

 flight, bypassing tree trunks and pjrramid 

 traps. Injury to fruit is greatest during periods 

 of warm weather, such as occurred from June 5 

 through June 9 in the Conway orchard in 1996 



(Figure 2). It appears that during this time 

 period, most curculios arrived in tree canopies 

 by flight and not by crawling up tree trunks (or 

 up pyramid traps). 



What might be a solution to this 

 shortcoming of pyramid traps during warm 

 weather? One solution might be to use a 

 powerful attractive odor in conjunction with a 

 pyramid trap positioned next to a tree trunk 

 (see following articles). Another solution might 

 be to develop an effective odor-baited trap for 

 use in the tree canopy. We are working toward 

 both solutions. 



Acknowledgments 



This work was supported by grants from the 

 USDA Northeast Regional IPM Competitive 

 Grants Program, the USDA SARE Program, 

 State/Federal IPM funds, and the New 

 England Tree Fruit Growers Research Com- 

 mittee. 



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Fruit Notes, Volume 62 (Number 1), Winter, 1997 



