204 EXPERIMENT STATION. [Jan. 



It is seeu that the upper south (piarter of the tree yiehled the 

 flattest apples each year, and usually by a considerable margin, 

 while the most elongated fruit comes from the lower portion of 

 the tree, and, in two of the years under consideration, on the 

 north side. On the whole the figures for the different parts of 

 the tree support the theory already presented that the elongation 

 is due to relatively cold weather, and gives support to the idea 

 that the heat of the sun has much to do with the temperature 

 of the tree itself and prol^ably the development of the fruit. 



In the Baldwins the relative rank is as follows for both j'ears: 

 upper south, uj^per north, lower south, lower north. 



On Sizk. 



The size of an apple is determined by several factors. Each 

 variety has its individuality in this respect. Culture is impor- 

 tant, an abundance of nitrogenous fertilizers and an abundant 

 supply of moisture being favorable to the attainment of large 

 size. An excessively heavy crop prevents the development of 

 full size of the individuals, but a light crop does not seem 

 favorable to any larger fruit than a moderate one. Young trees 

 usually bear larger fruit than mature ones, while in very old 

 trees the fruit is commonly inferior in size. The differences 

 due to age are probal)ly in considerable degree at least due to 

 the influences already mentioned. 



Aside from these influences the summer temjDcrature seems 

 to have considerable influence. Some evidence on this point 

 was presented in an earlier paper.^ Table 4 (]iage 203) gives 

 further data on this point. 



The mean summer temperatures at Amherst were as follows: 

 1908, .58.8°; 1900, .50.7°; 1910, .58.9°. 



The size of the apples is in a general way in accordance with 

 these tem])eratures. 



In 1910 the apples were much larger than in 1908. while the 

 temperature was ]iraetically the same. This may be due to 

 increased amounts of fertilizer which have been :i]i]iliod. The 

 orchard was lined in the spring of 1909, and this may have had 



• Report Massachusetts Experiment Station, 22, pp. 204, 211 (1909). 



