58 



Bulletin 393 



RELATION BETWEEN AMOUNT OF BLOOM AND SET OF FRUIT 



In the spring of 19 16 most of the mature trees in the station orchard 

 at Ithaca produced a heavy bloom. Individual limbs on many of the trees, 

 however, bore relatively few flowers. A number of such limbs, with a 

 light bloom, were labeled. Corresponding limbs with a heavy bloom, 

 but otherwise like the former — having a similar exposure, and arising 

 from the same parent limb — were also labeled. After the June drop, 

 the total number of flower-bearing spurs on each limb was obtained, 

 together with the number of spurs that had set fruit. The data from some 

 of the branches are recorded in table 8 : 



TABLE 8. Percentage of Spurs Setting Fruit on Limbs with Heavy Bloom 



AND on Those with Light Bloom 



Variety 



Baldwin, tree i 

 Baldwin, tree 2 



Fallawater 



Westfield 



Total 



Limbs with light bloom 



Num- 

 ber of 

 spurs 



52 



47 

 21 



25 



145 



Num- 

 ber 

 set 



40 



38 

 10 



19 



107 



Per- 

 centage 

 set 



76.9 

 80.8 

 47.6 

 76.0 



73-8 



Limbs with heavy bloom 



Num- 

 ber of 

 spurs 



116 



76 



255 

 250 



697 



Num- 

 ber 

 set 



18 



39 

 21 

 20 



98 



Per- 

 centage 

 set 



155 



51-3 



8.2 



8.0 



14. 1 



A larger percentage of spurs set fruit in the limbs with the relatively 

 light bloom. This fact is easily apparent on inspection, even without 

 accurate counts. Hence, only a relatively few limbs were removed from 

 the trees to obtain records, the remainder being used for other purposes. 

 An explanation for the results obtained is afforded by subsequent 

 observations. 



SET OF FRUIT ON LIMBS WITH LARGE LEAVES AND ON LIMBS WITH 



SMALL LEAVES 



It is not uncommon to find individual limbs with leaves noticeably 

 smaller than those on the remaining limbs of the same tree. In the spring 

 of 19 1 6, such small-leaved limbs which had produced a heavy bloom were 

 labeled. Limbs with normal leaves, but otherwise similar, were likewise 

 labeled. The percentage of flower-bearing spurs that set fruit was deter- 

 mined for each group of branches. Data of several of the many limbs 

 labeled are contained in table 9 : 



172 



