414 FIELD CROPS FOR THE COTTON-BELT 



Louisiana is: First year, corn with cowpeas sown broad- 

 cast at the last cultivation; second year, sugar-cane from 

 planted cane; third year, sugar-cane from old stubble. On 

 rich land a second crop of " stubble cane" is often grown. 



As a rule the entire crop of cowpeas should be plowed 

 under. The Louisiana Sugar Station secured an increase 

 of 7.4 tons of cane to the acre from plowing under the en- 

 tire growth of cowpeas as compared with plowing under 

 only the cowpea stubble. 



The Florida Station recommends sweet potatoes or 

 velvet beans as crops to precede sugar-cane in that State. 



514. Fertilizers. There are few crops so exhaustive 

 of soil nitrogen as sugar-cane. The tonnage of dry matter 

 removed to the acre is greater than is generally taken 

 from the land with other crops. In addition the leaves 

 and tops are usually burned in the field and the nitrogen 

 they contain is thus lost. While in most cases the nitrogen 

 can be profitably returned to the soil in commercial fer- 

 tilizers it can be even more profitably returned by plowing 

 under, every third or fourth year, a luxuriant growth of 

 cowpeas or velvet beans. 



Commercial materials that may be used as sources of 

 nitrogen are cotton-seed meal, dried blood, tankage, ni- 

 trate of soda, and sulfate of ammonia. The first three are 

 organic materials. The nitrogen in these materials is not 

 so readily soluble as that in the mineral fertilizers, and 

 for this reason the organic materials are usually preferred 

 on sandy soils that are subjected to heavy leaching. If 

 quick results are desired, the nitrate of soda or sulfate of 

 ammonia should be applied. 



The need for phosphoric acid in the sugar-cane belt is 

 quite general and as a rule it is second in importance to 

 nitrogen. It is supplied in the form of acid phosphate. 



