A STUDY OF VARIATION IN THE APPLE 



W. J. YOUNG 



Assistant Horticulturist, Washington Experiment Station 



As a rule the subject of variation in the several char- 

 acters of the apple has been given but incidental attention, 

 and that usually in connection with the study of other 

 problems. As a result the literature on the subject is of 

 a fragmentary character consisting usually of a few ob- 

 servations here and there in papers dealing with other 

 subjects. 



It is perhaps worth while to note a few of the investi- 

 gations which have thrown some light in an incidental 

 way upon the causes of variation in apples. In fertilizer 

 tests which were made at the New York Geneva station 1 

 and elsewhere, no well-defined and uniform influence of 

 the various elements of plant food upon the color could 

 be detected, though the New York station reports more 

 decided results in seasons when the natural conditions 

 were unfavorable to the development of highly colored 

 fruit. In the comparison of tillage and sod mulch in an 

 apple orchard, also conducted by the New York Geneva 

 station, 2 it was found that the fruit from an orchard in 

 sod was more highly colored and matured one to three 

 weeks earlier than that from the tilled plot, though the 

 latter was better in quality and kept four weeks longer in 

 common storage. The influence of the stock upon the 

 character of the fruit is a matter of much obscurity, the 

 investigation of which presents such difficulties that it 

 has received little attention. The effect of pollination 

 also is still far from settled. It was thought at one time 

 that the characters of the fruit were profoundly modified 

 by the pollen received by the blossom. The data on this 



1 Bull. 289. 



595 



