Thinning the Fruit 301 



long period. Not infrequently peach-growers may think 

 they have a remarkably heavy set of fruit which will call for 

 extensive thinning, but by the time the "June drop" is over, 

 it may appear that the crop is very light. An excessively 

 heavy drop is commonly associated with some adverse 

 weather condition during the blossoming period. In any 

 event, when thinning is to be done it should be accomplished 

 before the pits begin to harden if the depleting effect on the 

 tree of an excessive crop is to be avoided. 



Though the proportionate weight of the pit to the entire 

 fruit is small, its composition is an important factor. The 

 relation of the size of the pit to the whole fruit varies widely 

 in different varieties, ranging from about 3 per cent in weight 

 in some sorts to as high as 7 and 8 per cent in Mountain Rose, 

 Early Crawford, and Elberta. However, the size of the pit 

 in a given variety is not greatly influenced by the size of 

 individual fruits. The small fruits borne on an overloaded 

 tree develop pits nearly as large in size as the much larger 

 fruits on a well-thinned tree. 



The composition of the flesh, stones, and kernels of peaches 

 at different times in the season as given by Bigelow and 

 Gore^ is of interest in the present connection, since the figures 

 offer a clear explanation for the advantages of early thinning. 

 In the work reported, the composition of each of six different 

 varieties of peaches at three different periods in the develop- 

 ment of the fruit is given. The varieties used were Triumph, 

 Rivers, Early Crawford, Elberta, Heath, and Smock. The 

 different periods in the seasonal development of the fruit for 

 v/hich the composition was determined represented the time 

 immediately following the "June drop"; when the stone 

 had hardened, that is, when it offered appreciable resistance 



1 Bur. of Chem. Bull. 97. 



