152 SOILS AND PLANT LIFE 



Woody, and the ears likewise smaller, while the kernels 

 are shorter, more flinty and less deeply dented, until 

 at last we encounter the characteristic flint com of the 

 northern regions. 



Notwithstanding the fact that the com plant has 

 adapted itself in a truly marvelous way to grow in a wide 

 range of climate, it is still extremely sensitive to even 

 slight changes in climatic conditions. Thus we frequently 

 find that if the seed is sent or taken to a distance no greater 

 than forty or fifty miles from the locality where it was 

 grown, it will not produce at all well for a year or two, 

 or until it has had time to adapt itself to the new climatic 

 conditions. Com growers are for this reason extremely 

 cautious about procuring seed from other localities than 

 their own. We may truthfully say that there is not only 

 a corn for each climate but for every locality as well. 



109. Climatic Requirements of the Corn Plant. — Cer- 

 tain climatic conditions are necessary to the best growth 

 of corn wherever it is cultivated. 



The soil must be warm when the seed is planted and it 

 should remain warm thereafter. While the growing season 

 may vary in length, the average temperature of both day 

 and night must be high. 



While the seed is germinating, and the plants are yet 

 small, much wet weather is detrimental. It makes the 

 ground cold, excludes oxygen, and the stand may be poor 

 owing to the rotting of the seed. If the seeds germinate 

 under this condition, the little plants form shallow root 

 systems and so become unable to make a vigorous growth 

 or to withstand dry weather. Wet weather, moreover, 

 interferes with cultivation and allows weeds to become 

 established. 



The months of July and August represent the critical 



