SOIL Af^D CLIMATIC ADAPTATIONS OF CORN 213 



poverished sandy soils should be planted frequently to 

 such crops as cowpeas, soybeans, velvet beans, or oats 

 and vetch, and occasionally the entire crop plowed under. 

 In addition it will usually be necessary to apply phosphatic 

 and potassic fertilizers. The eroded uplands should be 

 terraced and such cropping systems practiced as will 

 restore the nitrogen and vegetable matter. The sour 

 bottom lands should be drained and half a ton to a ton 

 of slacked lime added to the acre. The application of 

 rough manures to the compact clays greatly improves their 

 condition, especially when such an application is followed 

 by fall plowing. Until the productiveness of these un- 

 desirable corn soils has been increased tl^ey should not 

 be planted to corn. 



259. Soil type and crop variety." — There is no question 

 btit that there is a great difference in varieties of corn in 

 their adaptation to different soils. For example. Hickory 

 King corn will reach normal development on much thinner 

 soil than will Albemarle Prolific. The best use of the differ- 

 ent types of corn soil can be made only when the most 

 suitable varieties are grown. 



CLIMATIC ADAPTATION'S 



260. Factors of climate. — The principal elements 

 combining to determine the climate, of a given region 

 are rainfall, sunshine, and temperature. Wind and hu- 

 midity are minor climatic factors. The adaptability of 

 a given region for a particular crop is determined both by 

 the combination and distribution of these factors. In 

 corn-growing, their distribution is of special importance 

 in determining the length of the growing season. In fact 

 the climate favorable to corn is determined more by the 

 distribution than by the intensity of these factors. 



