ing on apple trees in Rice's orchard. We were disap- 

 pointed in this finding, especially because in a 1993 

 study, the fibers had shown strong repeUency for as 

 long as 3 months against deer feeding on Sitka spruce 

 seedlings in a plantation in McClinton, British Colum- 

 bia. 



Several factors may have been responsible for the 

 lack of repellency in our study. First, the number of 

 fibers used (four per tree) may have been too few to 

 provide effective repeUency, although employment of 

 more than four per tree would have been too expensive 

 for practical commercial use. Second, the fibers may 

 emit too little odor under cold winter weather tempera- 

 tures in New England to be effective against deer. 

 Perhaps they are better suited for use imder warmer 

 West Coast winter conditions. Third, the deer at Rice's 

 may have been so hungry for winter food that hunger 



compromised their instinctive fear of cougars. 



Despite this lack of encouraging result, we firmly 

 believe that improved knowledge of the chemical ecol- 

 ogy of predators of orchard pests such as deer and voles 

 will some day lead to development and fomiulation of 

 blends of predator odor that wiU indeed effectively 

 repel these orchard vertebrate pests, just as synthetic 

 plant and insect odors are now being used effectively in 

 managing orchard insect pests. 



A cknowledgments 



We thank Phero Tech Inc. for providing us with the 

 odorous fibers. This work was supported by the Mas- 

 sachusetts Society for Promoting Agriculture and the 

 USDA Northeast Regional IPM Program. 



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18 



Fru'n Nates, Fall, 1994 



