248 PROCEEDINGS OF THE OHIO ACADEMY OF SCIENCE. 



the rainfall passes the 3.00 inch mark the increase in the yield 

 with each variation of one-half inch in rain amounts to over 

 three. and one-half times as much, or 4.3 bushels per acre. 



These figures mean that near the critical rainfall point a 

 variation of one-fourth inch in July means a variation in the 

 value of the corn crop in Ohio of nearly $3,000,000. and that 

 a variation of one-half inch makes an average variation in the 

 value of the crop of over seven and one-half million dollars. 



The last item in the table indicates that when the rainfall 

 for July for the State of Ohio averages over 5.00 inches the 

 probable corn yield will be more than 2/ million bushels greater 

 than it would be if the rainfall averages less than 3.00 inches. 

 This is an increase in the value of the corn crop of $3.90 per 

 acre or an increase in the purchasing power of the farmers of 

 Ohio of $13,650,000 due to corn alone. This will allow for the 

 purchase of over 30,000 of the most popular priced automobiles, 

 with a nice little sum left over for repairs. 



Four greatest corn States. Of the total acreage of corn 

 in the United States 30% is grown in the four States of Indiana. 

 Illinois, Iowa, and Missouri. Of the total amount shipped out 

 of the County in which it is grown 60% is raised in these four 

 .States. The average area devoted to corn in these States is 30,- 

 325,300 and the average yield is 7,2 bushels per acre. 



In these States when the rainfall for July has averaged 

 between 2.0 and 2.5 inches the yield of corn has averaged 23 

 bushels per acre, and when the rainfall has been between 2.5 

 inches and 3.0 inches the yield has averaged 33 bushels per acre. 

 This increase of 10 bushels per acre with an increase of only 

 one-half inch of rain means an increase in the value of the corn 

 crop of $5 per acre or the interesting sum of $150,000,000. 



When the rainfall for July over the 8 great corn States of 

 the central part of the United States has averaged more than 4.4 

 inches the yield of corn has been greater by 500,000,000 bushels 

 than when the rainfall has been less than 3.4 inches. 



If corn is King surely rain is the "power behind the throne," 

 and when a variation of this amount in the amount of rainfall in 

 July can be shown to increase the value of the corn crop fully 



