234 SOILS AND FERTILIZERS 



Potatoes require liberal general manuring reenforced 

 with wood ashes or other potash fertilizers. In the 

 rotation they should follow grain or pasture land, pro- 

 vided the fertility of the soil is kept up. 



299. Sugar-beets. — This crop is more exacting in 

 its food demands than other root crop. Excessive 

 fertility is not conducive to a high content of sugar. 

 Soils in a medium state of fertility usually give the 

 best results. 78 Sugar-beets should not receive heavy 

 dressings of stable manure, because an abnormal 

 growth results. Nitrogenous fertilizers can be ap- 

 plied only in limited amounts, heavier dressings of 

 potash and phosphoric acid are more admissible. 

 When sugar-beets follow corn which has been manured, 

 or grain which has left the soil in an average state of 

 fertility, the food requirements are well met. 



300. Roots. — Mangels are gross feeders and re- 

 move a larger amount of fertility from the soil than 

 any other farm crop. 73 When fed to stock and the 

 manure is returned to the soil they materially aid in 

 making the plant food more available for delicate 

 feeding crops. Mangels are better able to obtain their 

 phosphoric acid than are turnips and need the most 

 help in the way of nitrogen. Turnips are surface 

 feeders with stronger power of nitrogen assimilation 

 than the grains but with restricted power of phosphate 

 assimilation. Manures for turnips should be phos- 

 phatic in nature. 



