136 THE ESSENTIALS OF AGRICULTURE 



The best corn soils are well-drained, fertile loams which contain 

 a considerable vegetable matter. Corn is a heavy feeder, like- 

 wise a heavy producer, and to produce large yields it is neces- 

 sary to keep the soil in a high state of fertility by the frequent 

 addition of barnyard or green manure and by the use of legumes 

 in a crop rotation. Commercial fertilizers are extensively ap- 

 plied in the South and East, but on most of the corn-belt soils 

 it has not yet become necessary to use commercial fertilizers. 



FIG. 58. Weekley's Improved Dent corn. (Photograph from North 

 Carolina Agricultural College) 



164. Types of corn. There are six types of corn : dent, flint, 

 sweet, pop, soft, and pod corn. The first four only are of 

 commercial importance in America (Fig. 6). 



165. Dent corn. Probably 90 per cent of the corn of the 

 world is of the dent type (Figs. 57 and 58). The hard, flinty 

 portion of the kernel is at the sides, and the soft, starchy part 

 is at the crown or across the upper portion and in the center of 

 the kernel. In ripening, the starchy portion shrinks, leaving a 

 dent at the summit of each grain. This group is the one com- 

 monly cultivated in all parts of the corn-growing region of the 

 United States except in the North. 



166. Flint corn. The small amount of white or soft starch 

 contained in the kernel is at the center, while the crown and 

 sides are hard or flinty. The kernel does not dent in drying. 



