Fertilizers for Various Special Crops 349 



leguminous crop into it, not only improves the physical 

 quality of the soil, but enables a considerable accumula- 

 tion of nitrogen, frequently over one hundred pounds per 

 acre. The pea-vine lands, put in plant cane on account 

 of their excellent physical condition, not only yield up 

 readily the nitrogen stored up by the pea, but can also 

 assimilate larger quantities of plant-food applied as 

 fertilizer. Hence, such cane usually makes large crops. 

 Since nitrogen is the chief ingredient taken from the soil 

 by a crop of cane, it follows that with each successive 

 crop of cane grown on the land without the interjection 

 of the leguminous nitrogen there arises an increased de- 

 mand for nitrogen. Hence, stubble cane requires larger 

 quantities than plant cane, and the older the stubble, 

 the larger its requirements for this element." 



In reference to phosphoric acid, the results so far 

 indicate positively the value of this element in fertilizers 

 for sugar-cane on these soils, but the demand for this 

 ingredient is small in comparison to that for nitrogen, 

 36 pounds to the acre being ample for the crop. The 

 results further show that the soluble forms of phosphoric 

 acid are preferred. Inasmuch as the leguminous crop 

 does not add to the store of phosphoric acid in the soil, 

 it is equally needed by both plant and stubble cane. 



While potash has not been shown to be needed on 

 the land upon which the experiments were conducted, 

 because of the abundance of potash contained in the 

 soil, after continuous cropping of these and on lighter 

 soils this element should be included in the fertilizer. 



The application of fertilizers. 



For plant cane, a small quantity of readily available 

 fertilizer directly under and near the cane is highly 



