yO CYANAMID — MANUFACTURE, CHEMISTRY AND USES 



regard the disadvantageous action of lime nitrogen, such as 

 happens under applications of exceptionally large quantities in 

 pot experiments as either not occurring in agricultural practice 

 or as immediately disappearing. Practically, one cannot there- 

 fore regard lime nitrogen as a plant poison. It is to be 

 regarded as a fertilizer applicable in agricultural practice and 

 having a favorable action, although as is necessary with barn 

 manure, green fertilizers, bone-meal, horn meal, etc., the nitro- 

 gen contained in it must be converted by bacterial activity into 

 ammonia and nitric acid in order that it may serve as plant 

 food. 



"2. If lime nitrogen is applied in normal quantities, as com- 

 pared with other fertilizer materials, distributed as uniformly 

 as possible upon the soil, and worked in well with deep-acting 

 tools, it exerts no harmful influence even when applied im- 

 mediately before sowing of the seed. The idea that lime- 

 nitrogen must be completely, or at least to a great extent, 

 converted into ammonia or nitric acid before it comes into con- 

 tact with the seed is wrong, although it is possible that the action 

 of lime nitrogen in many cases can be increased if it is applied 

 8 or 14 days before sowing of the seed. 



''3. Lime nitrogen in ordinary field practice can act harm- 

 fully only when conditions are such that a part of the calcium 

 cyanamide suffers an unnormal decomposition. Conditions 

 under which this can happen are present especially in acid moor 

 soils or in soils which tend to become acid, or soils very rich in 

 humus, and therefore very poor in lime. It is known that 

 moor soils acts otherwise than normal towards other nitrogen 

 fertilizers as well. Sulphate of ammonia has an unfavorable 

 action upon acid soils. In order to avoid these unfavorable 

 conditions of acid soils previous liming is necessary. 



"4. Like all organic nitrogen fertilizers, green substances, 

 barn manure, horn meal, etc., the conversion into ammonia and 

 nitric acid is necessary in order to yield nitrogen assimilable 

 by plants, and like ammonia (although many plants take it up 

 and use it as such), for most plants it has its full effect only 



