8 VEGETABLE GROWING. 



NITROGEN. 



Iii its natural state nitrogen occurs as an atmos- 

 pheric gas, and as such it is not available as a fertili- 

 zer. When the term is used in speaking of a fertili- 

 zer, we simply mean that it is in some combination 

 with other elements that hold it in the form of a solid. 



The different forms in which nitrogen occurs as a 

 fertilizer are : First, as organic matter, either vegeta- 

 ble or animal ; e. g., tobacco stems, cotton-seed meal, 

 dried blood and tankage. Second, as nitrates ; e. g., 

 nitrate of soda, nitrate of potash, etc. Third, in the 

 form of ammonia compounds ; e. <?., sulphate of am- 

 monia. In the reports of fertilizers, when the amount 

 is given, it is intended to imply how much of it would 

 be present if it were in the form of a gas. 



