2o8 



THE CEREALS IN AMERICA 



shown that while no relation could be traced between tempera 

 ture and yield of maize, a very direct relationship could be 

 traced between rainfall and yield. The yield did not depend 

 merely upon the total rainfall for the five growing months of 

 la May to September, 



ill g^^Sss§§§ig|sl§ but much depended 



upon the distribution. 

 The June, July and 

 August rainfall had 

 the greatest influence, 

 and of these July was 

 the most important. 

 The September rain- 

 fall had no noticeable 

 effect, while much 

 rainfall and cloudy 

 weather in April and 

 May decreased the 

 yield. A July rainfall of from 4.75 to 5.25, and a June, July 

 and August rainfall of 11.75 to 12.25 inches, was found most 

 desirable. The most favorable condition for the growth of maize 

 is comparatively heavy rains at considerable intervals, with clear 

 sunshiny weather in the meantime. 



A comparison of the average rainfall for July and the 

 average yield of naaize in bushels per acre in Ohio, 

 Indiana, Illinois, Iowa, Nebraska, Kansas, Missouri and 

 Kentucky. (After J. Warren Smith.) 



Average yield of maize in bushels per acre. 



Average precipitation in July in inches. 



II. THE SOIL AND ITS AMENDMENTS. 



282. Soil. — The yield of maize is greatly influenced by the 

 character of the soil, perhaps even more so than any other 

 cereal. Alluvial river bottom soil and tile drained swamps 

 furnish the best conditions. A large proportion of the maize 

 crop is grown on drift soil, but not all portions of the glaciated 

 land are equally well adapted to this crop, (i 15) In the Southern 

 States the red or chocolate-colored upland soils with red clay 

 subsoils are better for maize than the gray soils with yellow 

 clay subsoils.* For its best growth, maize requires a friable 



1 Ga. BuL 46, p. 73. 



