U. S. DEPARTMENT OV AGRICULTURE. 



BUREAU OF PLANT INDUSTRY -BULLETIN NO. 104. 



B. T. GAM.OWAV, Cliirf i,f liuicau. 



THE USE OF FELDSPATHIC ROCKS 



AS FERTILIZERS. 



BY 



ALLEKTON S. CUSIIMAN, 





Assistant Dikector, Okfick of Public Roads, and 

 Collaborator, Bureau of Plant Industry. 



Issued May 27, 1907. 



WASHINGTON: 

 government printing office. 



190Y. 



