194 THE BOOK OF ALFALFA 



In the corn belt, which may be said to extend from the 

 central meridian of Kansas to Pennsylvania, alfalfa used 

 in rotation will do much to prevent the disgrace of rais- 

 ing an average of but twenty or twenty-five bushels of 

 corn to the acre. And so in what were once famous 

 wheat belts, alfalfa will restore the crop records, if prop- 

 erly used in a rotation. 



ROTATION A NECESSITY 



Some experiment station men insist that where alfalfa 

 is allowed to stand for many years it will cease to have a 

 fertilizing value; that alfalfa draws heavily on the potash 

 and phosphoric acid in the soil, and will after, say, eight 

 or ten years begin to deplete it of these important ele- 

 ments. Therefore they insist that alfalfa should not be 

 allowed to stand for over six or eight years unless it is 

 given an annual top-dressing of manure. They favor 

 plowing up the alfalfa after about five years and crop- 

 ping to corn or cotton. 



Former Governor Hoard in speaking of the value of 

 alfalfa as compared with that of clover in a crop rotation 

 says that, "alfalfa having a much larger root development 

 goes deeper down, thoroughly subsoils the ground, brings 

 up phosphorus and potash from the lower strata, and 

 leaves much more vegetable matter to decay and furnish 

 humus. Nothing else we have ever tried equals alfalfa 

 for putting the soil in good tilth." 



SPREADS THE BACTERIA OVER THE FARM 



Men who are raising alfalfa for use in a regular rota- 

 tion never leave it over six years ; many prefer five, while 



