94 



Bulletin 393 



TABLE 46. Weights of Smaller Spurs Bearing Fruit with a Low Seed Value 

 AND OF Those Bearing Fruit with a High Seed Value 



Variety 



Baldwin 



Fallawater .... 

 Rhode Island . . 

 Tompkins King 



Westfield 



All varieties , 



A poorly fertilized flovv^er can develop into a fruit, provided it is borne 

 on a vigorous spur; a weak spur, on the other hand, will mature only 

 a fruit that is developing many good seeds. 



These data suggest that there is greater need for cross-pollination 

 when the flowers are produced on trees growing under conditions that are 

 unfavorable for the production of strong spurs, than for trees under 

 favorable conditions. It is well known that apple trees growing in sod 

 will usually produce less fruit than similar trees growing under cultiva- 

 tion. Do sod trees produce less vigorous spurs than cultivated trees, 

 and consequently demand better fertilization of the flowers to insure a 

 set of fruit ? 



The following observations may throw some light on this question. A 

 large number of apples from a mature Tompkins King tree growing in sod 

 contained an average of 6.1 seeds. Fruits from a tree of the same age and 

 variety growing in a cultivated orchard had an average of 3.8 seeds. The 

 orchards in question were about half a mile apart. In both, the oppor- 

 tunities for cross-poUination were good. It seems reasonable to suppose 



208 



