1911.] PUBLIC DOCUMENT — No. 31. 197 



A study of this table shows some positive signs of indiviJual- 

 ily ill the trees in the characters of size, form and i^rodiictive- 

 iiess. Size is of course considerably affected by the number of 

 npples borne, though not as much as usual in this case, as the 

 trees have not matured a very heavy crop during the period of 

 observation. The marked seasonal fluctuation in size will be 

 considered later. We can say that Ben Davis trees 7 and 2 show 

 a tendency to bear large apples and trees 3 and 5 a tendency 

 to bear smaller fruit, though in 1910 tree 5 bore the largest 

 fruit of any, but at the same time the crop was lightest of all. 

 Among the three Baldwins, the rank has been the same each 

 year, in spite of the fluctuations in productiveness. In varia- 

 bility there are no constant difl'erences. In the Ben Davis there 

 seems to be a relation between variability and number of apples 

 produced, the greater the number of apples the greater the 

 standard deviation and coefficient of variability, — a relation 

 that is to be expected. 



In form, the situation is much the same. Ben Davis tree 7, 

 which produced the largest apples, has invariably borne the flat- 

 test ones, usually by a considerable margin. Tree 2 shows a 

 fairly constant character of producing more elongated apples 

 than its fellows. In the Baldwins, also, there are sigTis of slight 

 difi^erences between the trees. 



The variation in number of apples borne by the different 

 trees is great. Ben Davis tree 8 has averaged about three times 

 as many apjilcs as tree 5, and they have been larger. A part of 

 this dili'crence is due to thc^ fact that tree 8 is somewhat larger 

 llian tree 5, but the difference in size is not enough to account 

 for all the difl"erence in productiveness. 



Productiveness is one of the most important qualities of a 

 variety or individual tree. If the tree does not produce at least 

 n fair crop of fruit, all other valuable qualities it may possess 

 lose their attractiveness to the commercial grower, while great 

 ])roductiveness covers a multitude of deficiencies. Other inves- 

 tigations, and common observations as well, have shown very 

 marked diiferences in the bearing ability of different trees.^ 

 In our opinion, these differences, as well as any others which 

 may occur, are generally due to one or more of four influences: 



' See Macoun, Report Central Experiment Farm for 1903, p. 102. 



