254 SOILS AND FERTILIZERS 



of inoculation consists in first multiplying the organ- 

 isms in water containing nutritive substances, and 

 then sprinkling the seeds with this solution diluted. 

 Inoculation with soil from a field where clover or 

 lupines have previously been grown has also been suc- 

 cessful, particularly in reclaiming sandy waste lands 

 where mineral fertilizers containing potash and phos- 

 phates are used to furnish these elements of plant food, 

 while the more expensive nitrogen is acquired indi- 

 rectly from the air through the clover. Soils in a 

 high state of productiveness are not usually in need 

 of inoculation as they already contain all of the essen- 

 tial soil organisms. 



340. Cultivation for Special Crops. While the 

 general principles of cultivation apply to all crops, the 

 extent to which loosening or compacting of a soil 

 should be carried, must be determined by the charac- 

 ter of the soil and the crop that is to be produced. 

 The methods of cultivation must be varied to meet 

 the requirements of different soils and different crops. 

 The physical requirements of the soil for general farm 

 crops are discussed in Chapters I. and XL For the 

 production of a special crop, the cultivation must be 

 adapted to the specific requirements of that crop. A 

 knowledge of the requirements can best be obtained 

 by a study of the subject as based upon experimental 

 evidence. The cultivation of an untried crop should 

 not be attempted on a large scale without a knowledge 

 of the food requirements and the most suitable soil 

 conditions. The production of sugar beets for 



