arbitrarily because they gave the highest R^ values 

 for rainfall and sunshine data, i.e., best represented 

 the effects of these conditions. Rainfall generally 

 increased the R^ values significantly, showing that 

 more rainfall produced less scald. (It is usually 

 cooler when it is raining, but the effects on any as- 

 sociated low temperatures have already been re- 

 moved in the equations.) Sunshine had small ef- 

 fects on scald susceptibility, with sunnier days in 

 early Fall decreasing scald. 



These results show that low temperature (es- 

 pecially below SCF), adequate rainfall, and sunny 

 days all reduce scald susceptibility of Delicious 



apples grown in Massachusetts. Such years should 

 produce fruit with relatively low scald susceptibil- 

 ity; whereas warm, dry years will produce fruit with 

 more susceptibility, especially if it is cloudy (or if 

 trees have a thick canopy of leaves). Collectively, 

 we have accounted for about two-thirds of scald 

 variation with these measurements. 



In follow-up articles we shall compare the rela- 

 tionships in Massachusetts with those inother parts 

 of the world, consider some cultivars, other than 

 Delicious, and examine the prospects for predict- 

 ing scald susceptibility from measurements such as 

 these. 



vL* •sl^ •S^ •^ •^ 



•^ 0^ •^ •^ #^ 



Fruit Notes, Fall, 1995 



