Jan. 21. 1918 Irrigation Experiments on Apple-Spot Diseases 



117 



The results obtained on Grimes apples in 191 5 are shown in graphic 

 manner in figure 3. The contrasts for the season are similar to those 

 obtained on September 29. 



EXPERIMENTS ON GRIMES APPLES IN 1916 



In 1 91 6 the experiments were continued in the Grimes orchard de- 

 scribed above. Five trees were included in each plat. It was possible 



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Fig. 4.— Diagram showing soil-moisture conditions in irrigated plats of Grimes apples in 1916. The results 

 show the average percentage of saturation for each half month based on the average of soil samples at 

 depths of 24 and 36 inches. Plat i received heavy irrigation throughout the season; plat 2, medium; 

 plat 3, light; plat 4, medium till late in July, then heavy; plat 5, medium in June, heavy in July, and 

 light in August and September; and plat 6, heavy throughout, with the exception of a sudden drop to 

 medium in July. 



to carry out the irrigation schedule much more satisfactorily than in 

 the preceding year. The soil-moisture conditions for the season are 

 shown in figure 4. 



The fruit on plat 3 was noticeably smaller than that on the other plats 

 as early as August i , and by the close of the season the effects of irriga- 

 tion were quite evident in the size of the fruit from the various plats. At 

 picking time the fruit on plat 3 was found to be somewhat riper and more 

 highly colored than that on the other plats. The apples were picked 



