go HarsJiberger. — Maize . 



CHAPTER II. 

 Origin. 



A. Meteorological Proofs. 



THE conditions most favorable to the development of the 

 maize plant are long summers with sunny skies, hot 

 days and nights, and sufficient rain to supply the 

 demands of the rapidly- growing crop. The following table 

 gives an idea of the best temperature for growth. With a 

 temperature of. 



45°-5°° ^e yield was 40.8 per cent, of total crop. 



45°-55° « « 75-9 



45°-6o° " " 87.3 

 These figures refer to the year 1880. 1 The range of tem- 

 perature for the best development of the crop seems to be 

 between 45 F. (7 C.) and 65 F. (18 C), calculated in 

 terms of mean annual temperature, but the largest returns 

 resulted with a temperature in the month of July corre- 

 sponding to from 75 to 8o° F.; 961,123,938 bushels of the 

 1,754,861,535 bushels being the return in those regions having 

 the July temperature between 75 F. (24° C.) and 8o° F. 

 (26.7 C). The largest return was obtained in those localities 

 where the rainfall amounted to from thirty to fifty inches. 



30 to 45 inches yielded 63.4 per cent, of total crop. 



30 to 50 " " 86.8 



The largest absolute yield corresponded to a rainfall in the 

 spring and summer months of twenty to twenty-five inches. 

 The return was 1,143,239,093 bushels of the total crop, 1,754,- 

 861,535 bushels. Frost kills the plant in all its stages, and 

 the crop does not flourish where the nights are cool, no 



1 Census Report U. S., Agricultural Productions, 1S80. 



