1258 



EARLE V. HARDENBURG 



Macoun (1905) did not test the influence of frequency of spraying, but by 

 spraying four times in 1901 and in 1902, and five times in 1904, he obtained 

 an average increased yield, for the three years, of 94.5 bushels per acre. 



In spite of the loss of millions of dollars to the growers in New York 

 caused by the occurrence of blight every two or three years, and in spite of 

 the proved value of bordeaux mixture as a preventive of this disease, rela- 

 tively few growers make a practice of using a fungicide. Altho blight 

 has frequently been epiphytotic in all four of the regions surveyed except 

 Franklin and Clinton Counties, only one-third of the growers on Long 

 Island in 1912, 5 per cent in Steuben County in 1912, and 25 per cent 

 in Monroe County in 1913, sprayed their crops with a fungicide. 

 Occasional attacks of blight have been observed in Franklin and Clin- 

 ton Counties, but epiphyte tics are practically unknown; and even when 

 the fungus is present on the foliage, it seldom attacks the tubers to any 

 serious extent in this region. Only 1 per cent of the growers in this region 

 sprayed for blight prevention in 1913. So few growers used fungicide in 

 Steuben, Monroe, and Franklin and Clinton Counties, that the influence of 

 frequency on yield could not be studied in detail. The extent to which 

 insecticides and fungicides were used in the four regions, and the average 

 yields per acre under the various treatments, are given in table 83. In 



TABLE 83. SUMMARY OF SPRAYING IN THE FOUR REGIONS SURVEYED 



this table, a reliable criterion of the beneficial effects of spraying with fungi- 

 cide is not evident in those cases in which the percentage of growers 

 following any one of the three practices was below 15. 



Spraying on Long Island 



Spraying was done to a greater extent on Long Island than in the other 

 three districts surveyed. Only 9 growers out of 316 did not spray at all in 

 1912. About one-third of all the growers used a fungicide for the control 

 of blight, tipburn, and flea beetles. Ten per cent'of the growers reported 



