Jan. 21, 191S Irrigation Experiments on Apple-Spot Diseases 



121 



The first picking was made on September 3, when the apples were 

 rather green, a second on September 17, when they were right for 

 commercial picking; and a third, October i when the fruit was dead 

 ripe. In most cases a bushel of apples was secured from each tree at 

 each picking. There was practically no bitter-pit on the fruit at picking 

 time. The apples were placed in cellar storage at an average tempera- 

 ture of about 47° F., and notes were taken November 10. The results 

 are given in Table VI. 



All apples more than 2% inches in diameter were counted as large, 

 and the others as small. There was little contrast as to size in the fruit 



Flo. 7. — Diagram shor/ing the soil-moisture conditious iu irrigated plats of Jonathan apples in 1915. The 

 average percentage of saturation is given for each half month and is based on soil samples taken at 

 a depth of 16 inches. Plat i was to receive heavy irrigation throughout the season; plat 2, medium; 

 plat 3, light; plat 4, mediiun in August, then heavy; and plat 5, heavy till August i, then light. The 

 schedule was followed as closely as the water supply ^v■ould allow. 



of the different pickings, and all three were combined to obtain the data 

 given on size. 



The large apples again have much more bitter-pit than the small ones. 

 The apples of the first picking had more than twice as much bitter-pit as 

 those of the second and those of the second several times more than those 

 of the third. It might be suggested that a part of this contrast should be 

 attributed to the fact that the earlier pickings had been in storage longer, 

 but the later development of the disease in storage gives no support for 

 this hypothesis. The more mature fruit was apparently much less sus- 



