Comparison of Ladd Traps, Red Spheres, 

 and Yellow Panels for Capturing 

 Apple Maggot Flies in Commercial 

 Apple Orchards 



Juan Rull and Ronald Prokopy 



Department of Entomology, University of Massachusetts 



In a recent study in commercial apple 

 orchards, it was found that sticky red spheres 

 baited with butyl hexanoate caught four times 

 more apple maggot flies (AMF) than unbaited 

 red spheres. However, not everyone agrees 

 that baited red spheres are the best AMF trap. 

 For example, studies carried out in the western 

 U.S. seem to place sticky Ladd traps as being 

 equal or superior to sticky red spheres. Ladd 

 traps consist of a square yellow panel with a red 



sphere m the center. The yellow panel is 

 believed to attract immature AMF whereas the 

 red sphere is believed to attract mature AMF. 

 Trap position is critical for effectiveness. We 

 speculated that Ladd traps in poor position 

 could have been more effective than red sphere 

 traps in poor position in studies favoring Ladd 

 traps as being superior. Finally, some of the 

 studies on Ladd traps were not performed in 

 commercial orchards, where incoming AMF 



Fruit Notes, Volume 62 (Number 4), Fail, 1997 



