CASSAVA 459 



small to be dangerous to man or to live-stock. The greater 

 part of the prussic acid is contained in the bark or skin of 

 the root and in its outer layers. 



437. Soils and fertilizers. Cassava requires a rather 

 fertile, loose, sandy soil. A sandy soil is not only necessary 

 for the best growth of the plant, but also in order that the 

 roots may be easily pulled. The land must be well drained 

 and warm, so as to make the season of growth as long as 

 possible. Cassava thrives on soil too sandy and dry for 

 corn and may be regarded as a drought-resistant crop. 



It is best to furnish the nitrogen for cassava by grow- 

 ing a preceding crop of cowpeas or velvet beans. In case 

 cassava is not preceded by a leguminous crop, it should 

 be fertilized with a complete fertilizer, such as the fol- 

 lowing : 



200 Ib. acid phosphate per acre, 

 50 Ib. muriate of potash or 200 Ib. of kainit, and 

 200 Ib. cotton-seed meal. 



In a single test in Florida, it was found better to apply 

 all of the fertilizer before planting than to divide it into 

 several applications. 



438. Preparation, propagation, and cultivation. Prepa- 

 ration consists in broadcast or level plowing and harrow- 

 ing. Plowing need not be very deep, for this would have 

 the effect of making the roots grow deeper in the soil and 

 hence make the pulling of the roots more difficult. The 

 land should be marked off in checks 4 feet each way, 

 and the fertilizer drilled in and mixed. At the intersec- 

 tion of the furrows or marks, the sections of stem contain- 

 ing the eyes or buds should be dropped, stepped on, and 

 covered with 2 to 4 inches of soil. 



