study by Martin Aluja indicated that fruit-foraging 

 AMF have a propensity to move upward when forag- 

 ing for fruit and spend more time foraging in the 

 middle and upper part of the tree canopy. 



Conclusions 



Our findings indicate that the performance of 

 sticky red spheres whether baited or not with syn- 

 thetic food and fruit odor, is affected strongly by 

 clearing of surrounding foliage or fruit, as well as by 

 height of placement in the tree canopy. Baited spheres 

 capture more flies than unbailed spheres under all 

 conditions. To intercept AMF immigrating into or- 

 chards, spheres should be placed in the middle 1/3 or 

 upper 1/3 of the tree canopy and surrounded by as 

 much foliage and fruit as possible except for a 10- 

 inch radius around. This placement will optimize the 

 finding of spheres by AMF within a tree. 



Selected References 



Drummond, F., E. Groden, and R. J. Prokopy, 1984. 

 Comparative efficacy and optimal positioning of traps 

 for monitoring apple maggot flies (Diptera: 

 Tephritidae). Environmental Entomology 13: 232 - 

 235. 



Reissig, W. H. 1975. Performance of apple maggot 

 traps in various apple tree canopy positions. Journal 

 of Economic Entomology 68: 534 - 538. 



Acknowledgments 



We thank Tom Clark for the use of his orchard. 

 This work was supported by the Northeast Regional 

 Project on Integrated Management of Apple Pests 

 (NE-156). 



vj>» •^ •^ •X* vl> 

 •^ 0^ 0^ 0^ 0^ 



Fruit Notes, Summer, 1993 



11 



