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SCIENTIFIC AGRICULTURE 



November. 1921 



Fertilizers and Canada's Agricultural Future 



By H. G. BELL, 



Director, Soil and Crop Improvement 



Bureau, Canadian Fertilizer 



Association, Toronto. 



Sometimes a veil of mystery seems to 

 bechnul the whole feitility question— es- 

 peciallv when a discussion of fertilizers 

 is undertaken. No doubt tl)is tinge of 

 mystery comes partly from the rather in- 

 explicable returns which c(mie from the 

 application of a small amount of fertilizer 

 under most favorable conditions. We feel 

 tliat too much has been made of the mys- 

 tery side of the question in times past, and 

 that the best interests of the farm will be 

 seived by a closer acquaintance with fer- 

 tilizers, their composition and best use. 

 What Fertilizers Are. 



Fertilizers are carriers of exactly the 

 same plantfood constituents as are found 

 in the crop, in the soil, and in stock man- 

 ure but in more concentrated and available 

 forms. The materials which ca:ry these 

 plant foods in fertilizers come from various 

 parts of the world, from primary products, 

 from by-products, from waste material. It 

 may serve a good purpose for us to actual- 

 ly catalogue the leading sources of nitro- 

 gen, phosphoric avid and potash: 



Nitrogen comes from hlood and tankage, 

 waste products of the packing-house indus- 

 try and both carriers of a considerable per- 

 centage of available nitrogen. 



This element may come also from sul- 

 phate of ammonia, a by-product salt of the 

 coking industry. Sulphate of ammonia is 

 proving more and more useful in fertilizers 

 where nitrogen of fairly rapidly available 

 type is necessary. When using sulphate of 

 ammonia, one has to be careful to apply 

 lime in rotation sufficiently often to keep 

 the soil reaction neutral or alkaline, since 

 the ammonium salt tends to leave an acid 

 reacticm in the soil. Sulphate of ammonia 

 is proving especially valuable as a nitrogen 

 (•arrier for orchard crops. 



Ciiamamid, although a comparatively 

 new' product, is being so developed that it 

 can be used successfully in fertilizers as a 

 carrier of nitrogen. The nitrogen in its 

 primarv form in cyanamid. is closely con- 



nected with calcium and carbon. This ra- 

 pidly breaks down into an ammonia form 

 which changes in the soil to nitrates whicli 

 are directly available as plantfood. 



These four carriers of nitrogen are all 

 manufactured in Canada. There lias been 

 a considerable impoitation of nitrate of 

 Hoda in times past, — a soluble salt which 

 carries a relatively high percentage of avail- 

 able nitrogen. Where extraordinarily 

 quick action is necessary this salt provides 

 the plantfood in a very available form, but 

 for sandy soils and for crops requiring a 

 continuous supply of nitrogen it is prov- 

 ing more profitable to obtain a considerable 

 amount of the ammonia from more slowly 

 available forms. 



Phosphoric Acid may come fi-om any 

 one or more of the following three mat- 

 erials : 



First — Acid Phosphate. Acid Phosphate 

 is acidulated phosphate rock, generally im- 

 ported from Southern and Eastern states. 

 There are some deposits of phosphate rock 

 in our own country in the vicinity of King- 

 ston, Ont. and Buckingham, Que. In 

 the manufacture of acid phosphate, the 

 acidulation of the phosphate rock is car- 

 ried on only to that point where the phos- 

 phate of the rock is broken down to its 

 most soluble form, which is the mono-cal- 

 cic salt. Long-time experiments, chemical 

 studies, prove that the use of acid phos- 

 phate does not render the soil acid. Stu- 

 dents of chemistry will sometimes ques- 

 tion the necessity of acidulating rock when 

 it is a well known fact that as soon as the 

 mono-calcic phosphate mixes with the soil 

 it immediately reverts to less soluble forms, 

 but the whole object of the treatment is to 

 add an available form of phosphoric acid 

 which can distribute quickly and thor- 

 ougldy through the soil waters. The big 

 advantage is that when it does revert, 

 pliosphoric acid is mixed throughout the 

 top areas of tlie soil, wliere the plant feeds, 

 with a thoroughness far in excess of anv 



