treatment containing 5 ppm NAA plus 1 qt 

 Sevin XLR/ 100 gal. Accel plus Sevin ap- 

 peared to be a good combination for Mcintosh 

 at either petal fall or at the 1 0-mm stage. For 

 increased fruit size, application of this combi- 

 nation at the 10-mm stage is superior. Accel 

 used by itself is not a potent thinner when sued 

 at the current commercial rates. 



1994 Thinning Results with Fuji 



A block of six-year-old Akifu #1 Fuji was 

 selected at Chedco Orchard, Berlin, MA. 

 Accel at 20 and 40 g a.i./acre, Sevin XLR at 1 

 qt/ 100 gal, and 6 ppm NAA were applied alone 

 and in all combinations at the 10 mm stage of 

 fruit development. Accel alone did not thin 

 (Table 3). Sevin thinned only modestly when 

 used alone, but when combined with Accel it 

 thinned very well, which resulted in a large 

 increase in fruit size. NAA alone did not thin. 

 When combined with Sevin it thinned but fruit 

 size was increased only modestly. When NAA 

 was combined with Accel there was no thin- 

 ning and there was a dramatic reduction in fruit 

 size. Much of the decrease in fruit size was 



when the temperature was about 80"F. 

 Petal-fall applications of either Sevin 

 or Accel alone were not very effec- 

 tive, but when combined, they reduced 

 fruit load to an appropriate level 

 (Table 2). Accel application at the 10 

 mm stage caused only modest thin- 

 ning, whereas Sevin or Sevin applica- 

 tion with Accel reduced crop load ef- 

 fectively. Accel plus Sevin at the 10- 

 mm stage increased fruit size to the 

 greatest extent. The standard thinning 

 treatment of 5 ppm NAA plus Sevin 

 was the most effective thinner, while 

 Accel plus Sevin increased fruit size 

 most. A double application of Accel, 

 at petal fall and again at the 10-mm 

 stage, was no more effective than a 

 single application at either time. 

 Warm temperatures at and following 

 application allowed thinners to work. 

 The best thinning treatment in this 

 experiment was the standard thinning 



Fru/r Notes, Spring, 1995 



