46 Bulletin 393 



series of observations and experiments that have been in progress during 

 the past three seasons. The results obtained during this time are pre- 

 sented in this bulletin. 



SURVEY OF LITERATURE 



In early times the success or failure of the fruit crop was attributed 

 largely to weather conditions. This may be inferred from folklore similar 

 to that recorded by Bull (1878).- The conditions mentioned in the fol- 

 lowing quotation, for example, involve an early spring and rather dry 



weather: 



March dust on an apple leaf, 

 Brings all kinds of fruit to grief. 



In another quotation, emphasis is placed on the time of blooming, 

 which likewise involves weather conditions: 



If the apple tree blossoms in March, 

 For barrels of cider you need not sarch, 

 But if the apple tree blossoms in May, 

 You can eat apple dumplings every day. 



The chances of having cold, windy, cloudy, and rainy weather during 

 blooming time would be greater in March than in May. Besides, the 

 weather conditions immediately after fertilization of the flowers would 

 probably be more favorable for fruit development during a late spring 

 than during an early one. 



The following extracts from Langley (1729 a) are interesting since he 



attempts to explain the observed phenomenon on a physiological basis. 



Referring to the fact that "there are many excellent Kinds of Fruits 



which produce great Plenty of Blossoms, and but very little Fruit," 



Langley writes: 



This Sterility is caused by the too great Abundance of Wood, which, when 'tis 

 cover'd over with its beautiful Blossoms, requires a much greater Quantity of Nourish- 

 ment than the Roots are at that Time able to communicate, and thereby, for want 

 of proper Nourishment, the Embryo Fruits are starved, and more especially when 

 the Soil and Spring are both dry, their Perspirations [transpirations] being then greatest; 

 and if Easterly Winds happen to blow at that Time, their very drying exhaling Nature, 

 is a further Help to the Destruction of the Fruit. 



This author also observed that some peaches in which the blossoms 

 open before the leaves, such as Old Newington, have a tendency to pro- 

 duce smaller crops of fruit than such varieties as Albemarle and Catherine, 

 which produce leaves with their blossoms. He believed that the leaves 

 "strongly attract Nourishment from the Roots to the Blossoms." 



Referring to the June drop, Langley (1729b) writes: 



Now [from May 20 to June 20] 'tis always seen that great 



Quantity of Fruit drops, altho' largely grown. Of this al' our late Authors on 



2 Dates in parenthesis refer to bibliography, pages H2 to 114. 



160 



