Abscission of Flowers and Fruits of the Apple 107 



4. Only three to seven per cent of the total ntimber of flowers finally 

 develop into fruits. 



5. If comparatively few flowers begin to develop fruits, the June drop 

 will be small ; if a large number of flowers begin development, the June 

 drop will be heavy. 



6. From one-sixth to one-third of the flower-bearing spurs finally set 

 fruit. 



7. The proportion of spurs that hold fruit after the June drop varies 

 in different trees of the same variety and on different limbs of the same 

 tree. These variations are not due entirely to the location of the limb 

 or to the angle at which it grows. 



8. A larger proportion of spurs set fruit on limbs that have produced 

 a relatively light bloom than on limbs that have produced a full bloom. 



9. Spurs on limbs with large leaves are more likely to set fruit than 

 spurs on limbs with small leaves. 



10. During 191 5 there was no consistent difference in fruitfulness 

 between the spurs arising from 19 13 wood and those arising from older 

 wood. Comparatively few spurs arising from lateral buds on 1914 wood 

 set fruit in 19 15. The shorter the terminal growth during 19 14, the 

 greater was the tendency for lateral buds to set fruit in 19 15. 



11. The spurs occurring near the end of a season's growth, or just 

 before a zone of weak buds, are the most likely to set fruit. As a rtile, 

 the spurs in the terminal half of a given season's growth set more 

 abundantly than spurs in the basal part. 



12. Spurs that lose all flowers and fruits during the first drop average 

 fewer flowers to the spur than those that hold fruit after the June drop. 



13. Spurs producing many flowers are more 'likely to set fruit than 

 those that produce a small number of flowers. 



14. A higher proportion of the flowers produced on spurs with many 

 flowers set fruit, than is the case with spurs producing few flowers. 



15. Spurs making more than one centimeter of growth during the 

 preceding season have a greater tendency to set fruit than those that 

 make less than one centimeter of growth. 



16. Spurs that finally set fruit are heavier than those that lose all their 

 flowers and fruits. Those that hold fruit until the June drop are heavier 

 than those that lose their flowers during the first drop. 



17. Spurs bearing two fruits weigh more than those bearing only one 

 fruit. 



18. A larger proportion of strong spurs set two fruits to the spur than 

 is the case with weak spurs. 



19. Spurs which produce many flowers are heavier than spurs which 

 are taken from the same limb but which produce few flowers. 



221 



