CORN 139 



have a well-pulverized surface and a firm subsurface, and should 

 be amply supplied with moisture and available plant food. The 

 proper depth of plowing varies with conditions ; fall plowing 

 should be deeper than spring plowing. An average of five to 

 six inches is a sufficient depth in the spring, whereas the same 

 soils may be profitably stirred to a depth of seven or eight inches 

 in the fall. Harrowing after each half day's plowing in the spring 

 is very important because the soil pulverizes easily at that time 

 and the loss of moisture is effectively checked. The best farmers 

 disk the ground several times and harrow it once before planting, 

 to pulverize, level, and compact the seed bed. 



Fall plowing has a number of advantages, such as (i) longer 

 and more complete exposure of the soil to the effects of frost, 

 thus providing a better physical structure ; (2) more time for the 

 decay of vegetable matter, which increases the supply of avail- 

 able plant food ; (3) closer connection between the plowed soil 

 and that beneath ; (4) exposure of injurious insects to birds or 

 to unfavorable weather. 



Fall-plowed land should not be disked or harrowed until early 

 spring ; otherwise it will become too compact, it will not catch 

 the rain and snow water so well, and it is much more inclined 

 to be blown than when left rough on the surface. Sod and 

 stubble lands should be plowed in the fall unless they are so 

 rolling as to wash badly or of such a nature as to be blown easily. 



When corn follows corn, the land is usually plowed in the 

 spring. Early spring plowing is preferable, as the soil has more 

 time to settle, a larger amount of moisture is retained, and more 

 plant food is made available. 



173. The importance of good seed. Of two varieties or strains 

 of corn growing side by side, one may produce a yield of ninety- 

 five bushels, the other thirty-five bushels. The difference is due 

 to something that one strain has and the other lacks. That some- 

 thing is the enlarged power to gather food from the soil and air 

 and to utilize the sun's rays in organizing this food into stalk, 

 leaf, and grain. It is this increased power which distinguishes 

 an improved or pure-bred plant from a poor plant. 



