Abscission of Flowers and Fruits of the Apple 



77 



TABLE 29. Lateral Spur Growth Produced by Setting and by Non-setting 



Spurs from a Baldwin Limb 



Amount of lateral growth 



Nc growth 



2 leaves 



3 leaves 



4 leaves 



5 centimeters 



Average weight of lateral growth 



Average weight of spurs minus lateral growth 



Produced by- 

 setting spurs 



6 

 20 

 20 



5 

 I 



I . 



2. 



35 grams 

 39 grams 



Produced by 

 non -setting spurs 



10 



13 

 14 



5 



o 



o . 79 gram 

 1 .31 grams 



carefully examined. The results obtained with a pair of similar limbs 

 from a Strawberry tree are recorded in table 30. One hundred of the 

 largest spurs from each limb are considered. 



TABLE 30. Lateral Growth Produced by Large Flower-bearing Spurs, 

 FROM Limbs Setting Few and from Those Setting Many Fruits 



Amount of lateral growth 



2 leaves 



3 leaves 



o . 5-5 centimeters 



5 . i-io centimeters 



10. 1-20 centimeters 



Over 20 centimeters 



Average weight of lateral growth 



Produced by 

 spurs from 



limbs setting 

 few fruits 



24 

 42 

 29 



5 

 o 

 o 



I .91 grams 



Produced by 



spurs from 



limbs setting 



many fruits 



12 



23 



34 



7 



10 



14 



3- 



70 grams 



According to the table, the spurs from the fruitful branches have a 

 tendency to produce more lateral growth than those from the less fruitful 

 limbs. The average weight of the lateral growth produced by the former 

 spurs is almost double that produced by the latter. 



These figures indicate that fruit-setting is not opposed by vegetative 

 activity as manifested by the amount of lateral spur growth. On the 

 contrary, they suggest that the conditions which favor such growth are 

 likewise favorable for the setting of fruit. 



One of the essential conditions for the forcing of the lateral buds 

 is an abundant supply of sap. It is well known that heavy pruning of an 

 apple tree during the dormant season stimulates the production of vigor- 

 ous shoots from the remaining growing points. Such pruning disturbs 

 the equilibrium between the top and the root systems, and as a result 

 there is an abundant supply of food and water for vigorous top growth. 



191 



