of Avaunt applied only to perimeter rows were about 

 as effective as sprays of Guthion applied only to 

 perimeter rows and about as effective as sprays of either 

 Guthion or Avaunt applied to all rows m preventing 

 injury to fruit on unsprayed rows 3, 5, and 7. Results 

 for PC suggest that sprays of Guthion applied to all 

 rows were slightly more effective than sprays of the 

 other three treatments in preventing mjury to fruit on 

 rows 3, 5, and 7, but differences among treatments in 

 such injury were not significant. 



Conclusions 



Results of this study suggest that under the weather 

 and pest pressure conditions that existed in six 

 commercial orchards in Massachusetts in 2001, sprays 

 of Avaunt (at standard recommended rate) were nearly 

 as effective as sprays of Guthion in controlling PC, 

 AMF, and summer LR. Moreover, sprays of either of 

 these insecticides applied only to the first and second 

 perimeter rows of plots were about as effective in 

 preventing injury by AMF and summer LR in 

 unsprayed intenor rows of plots as were sprays of these 



insecticides applied to all seven rows of plots. 

 Perimeter-row sprays were slightly less effective in 

 preventing penetration and injury by PC and were 

 ineffective in prevention penetration and damage by 

 potato leafhoppers on unsprayed interior rows of trees. 

 Recent studies in other states suggest that Avaunt 

 is just as effective as Guthion against PC but performs 

 inconsistently against AMF. Hence, for 2002, we plan 

 to repeat this study in the same six orchards to acquire 

 a second year of data on the performance of Avaunt 

 under Massachusetts conditions. 



Acknowledgements 



We thank Andrew Hamilton for applying all post- 

 petal-fall sprays and the six cooperating growers: Jerry 

 Bieme, Dave Bishop, Aaron Clark, Don Green, Tony 

 Lincoln, and Bob Tuttle. Thanks also to DuPont 

 Corporation for providing the Avaunt, and to Jaime 

 Pinero and Sara Dynok for preparing the figures. This 

 study was supported by a grant from the USDA 

 CSRJEES Crops at Risk Program, orchards in MA in 

 2001. 



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18 



Fruit Notes, Volume 66, 2001 



