INTERNAL BROWNING OF YELLOW NEWTOWN APPLE. X7 



badly browned after a season in cold storage. After the recMtds 

 of the work of three seasons were available, however, it was evi- 

 dent that this condition does not hold true. In certain inetances, 

 trees have produced sound fruit a number of years in succession, 

 while others have produced fruit with a tendency to bad browning 

 in successive years. But this condition by no means holds gener- 

 ally, and very often a tree which produces sound fruit one year will 

 produce fruit tending to brown very badly the next year. In other 

 words, it is impossible to predict what a tree will dq, Wsing the 

 prediction on its previous performance record. 



DEFOLIATION AND GIRDLING EXPERIMENTS. 



In order to obtain evidence, if possible, upon the internal condi- 

 tion of nutrition in the trees that are associated with the occurrence 

 of browning, it was planned during the summer of 1919 to vary the 

 nutritive conditions in different parts of the same tree and to deter- 

 mine the effect of these treatments on the development of internal 

 browning. 



Six trees were selected for special treatment, three of which 

 during the preceding year had produced fruit that tended to brown 

 badly and three of which had produced fruit that remained sound. 

 All trees were bearing heavy crops of fruit. 



Branches as nearly uniform as possible and ranging from 1 to 

 2^ inches in diameter were selected. On each tree certain branches 

 were girdled by removing a ring of bark one-eighth to one-fourth 

 inch wide around the branch near its base. Other adjacent and 

 similar branches were treated by removing about half the leaf area 

 from the branches. Partially defoliated branches in all cases were 

 well loaded with fruit, while in the cases of girdled branches the 

 number of apples on each branch was reduced by thinning until no 

 two fruits were closer together than 5 inches. All of this work was 

 done on June 26, 1919, when the fruit was about three-fourths of 

 an inch to 1 inch in diameter. Adjacent branches receiving no 

 treatment served as checks to the treated ones. 



Fruit on the girdled branches was very large at the time of pick- 

 ing, which was in the first week of October. It was yellow tinged 

 and well ripened and had a tendency to water core. The fruit on 

 branches that were partially defoliated, on the other hand, was 

 small and green in appearance at the time of picking. Normal 

 fruit on the same trees was intermediate in degree of apparent 

 maturity and in size. Chemical analyses made at the time of pick- 

 ing and again at the time of the inspection of the fruit upon its 

 removal from storage in May, 1920, showed that the fruit from 

 girdled limbs was markedly higher in both total sugar and in 



