154 SOILS AND PLANT LIFE 



As the ears become well developed, the supply of mois- 

 ture should diminish. This, too, is a matter of importance 

 since continued rains after this time prolong the season of 

 growth. In wet seasons, therefore, the crop is frequently 

 injured by early autumn frosts. 



110. Soil Requirements of the Corn Plant. — Com 

 requires a fertile, well-drained soil, containing a large 

 amount of humus. Owing to its vigorous growth, it 

 demands large amounts of the essential elements mentioned 

 in Section 7. Nitrogen, in particular, is rapidly removed 

 by it from the soil. Unless some means of renewing the 

 supply of nitrogen is provided, the yields of the succeeding 

 crops gradually decrease. In fact, we may say that the 

 rainfall of July and August and the supply of nitrogen in 

 the soil are the two factors which commonly influence the 

 production of the corn crop throughout the Com Belt. 



111. The Production of Corn. — The production of 

 com may be studied imder eight important heads : 



(1) Selection of the Seed. 



(2) Storage of the Seed. 



(3) Testing the Seed. 



(4) Grading the Seed. 



(5) Preparing the Seed Bed. 



(6) Planting the Seed. 



(7) Cultivation of the Crop. 



(8) Harvesting the Crop. 



112. Selection of the Seed. — In Chapter VII, and 

 particularly in Exercise 18, we learned some of the im- 

 portant points to look for in an ear of com and in the stalk 

 which bore it. We must now take up a more critical 

 study of the ear which we wish to use for seed. 



