14 



BULLETIN 1406, U. S. DEPARTMENT OF AGRICULTURE 



In order to determine as accurately as possible the changes in the 

 ground color of the fruit, the color chart shown as Plate I has been 

 used, the ground color of the fruit in the different growing 

 regions being compared with the colors on this chart. In order to 

 obtain the best comparison, holes were cut in the centers of the color 

 charts and the apples placed behind them, so that the same light was 

 available on the fruit surface as on the chart. 



Table 3 gives in summarized form the exact conditions of the 

 different varieties at the time each year when they were in opti- 

 mum picking condition in the various sections. The column headed 

 " Ground color " refers to the chart color. 



It is apparent that there is a marked variation in the ground 

 color of different varieties at the optimum picking date for each 

 variety. Jonathan, Ben Davis, and Winesap in all sections were 

 either color 3 or color 4 at the time they were ready to pick. 

 Delicious ranged from 2% to 4 at the different stations. Grimes 



Fig. 



-Change in firmness of flesh and size of Winesap apples, 1923 



Golden at the optimum picking date ranged from 2 at Eosslyn 

 in 1924 to 3 as the general color at picking time in most sec- 

 tions. Baldwin ranged from a color between 1 and 2 at Wenatchee 

 in 1924 and Eosslyn in 1923 to between 3 and 4 at Amherst 

 in 1923. Thus it is evident that the same changes in ground 

 color can not be applied for all varieties under all conditions. Of 

 the varieties under test, Ben Davis and Winesap became very yel* 

 low. Jonathan and Delicious became full yellow in certain sections 

 but remained with a decidedly greenish tinge in other sections. 

 Grimes Golden was rather green in some sections, whereas Baldwin 

 showed only a slight yellowing in all sections except Amherst in 

 1923. The Baldwin apple in most stations dropped very badly 

 before there was an appreciable yellowing in the ground color. 



A careful study of the data in Table 3 indicates that on the whole 

 the ground color becomes more yellow before picking time in the 

 regions where ripening is late and where the prevailing tempera- 



