REPORT OF TEE CHEMIST 161 



SESSIONAL PAPER No. 16 



For Cereals, Gi-ass: 



Dog-fish scrap 300 lbs. 



Nitrate of soda 100 " 



Superphosphate 300 " 



Muriate of potash .50 " 



AppHcation — 300 to SCO lbs. per acre. 



For Potatoes, Roots generally, and Clover: 



Dog-fish scrap 300 lbs. 



Nitrate of soda 50 " 



Superphosphate 400 '* 



Muriate of potash 150 " 



Application — 300 to 800 lbs. per acre. 



Dry sand or fine loam may be added to tlie mixed fertilizer to facilitate distribu- 

 tion. 



Probably the best plan of application is to broadcast the fertilizer on the thorough- 

 ly prepared land in the spring, previous to seeding, incorporating with tlie soil by 

 one or more harrowings. It has been found that fish refuse gives the best returns on 

 moderately light, warm, moist soils. 



Wliat is the value of the nitrogen and phosphoric acid in this scrap? This ques- 

 tion has been frequently submitted to us during the past few months, and it seems 

 desirable that an answer should be given here in conjunction with the foregoing in- 

 formation respecting the nature of this new fertilizing material. 



In the last bulletin on ' Commercial Fertilizers as Sold in Canada,' issyed by the 

 Inland Revenue Department, the following valuation is given: — 



Organic nitrogen in ground bone. fish, blood or tankage 16c. per lb. 

 Phosphoric acid, according to solubility, from . . . .1^ to 6c. " 



Until data obtained from actual trials in the field are available, we perhaps should 

 not be justified in affirming that this fish scrap should be placed in the same category 

 with the above-mentioned fertilizers; we might suppose, however, that both its nitro- 

 gen and phosphoric acid, in the absence of deterrent influences, will he found equally 

 available with those of these fertilizers. The question therefore is, are there any 

 factors of an unfavourable character in connection with this material? First, as 

 regards the degree of fineness. As pointed out, this is an important matter and 

 several of the samples give evidence that there is room for improvement in this 

 respect. The finer the material the more readily will the fertilizing elements be set 

 free in the soil. If the material contains much coarse bone, that is, pieces 1 inch to 

 1^ inches in length, it cannot be considered as being in the best condition for direct 

 application to the soil. 



Secondly, as fully explained in the text of this report, the presence of a large 

 quantity of oil is most undesirable, especially where large applications are made year 

 after year. In the greater niimber of the dog-fish refuse samples examined, the per- 

 centage of oil was undoubtedly too high. Very probably this will be materially de- 

 creased as methods of manufacture are improved — a matter which is now receiving 

 attention at the reduction works. 



After a very careful consideration of all these matters, the writer is inclined to 

 the opinion that the nitrogen in the pure dog-fish scrap, as represented by sample^ 

 examined, is not quite equal in value, agriculturally, to that in the better class of 

 organic fertilizers, and for this reason its price should be somewhat less. Provisionally, 

 we should place this reduction at two to three cents per lb., that is, a value of about 

 13c. per lb. The phosphoric acid should be worth in the neighbourhood of 5c, per 

 pound. 



This dog-fish refuse should prove a very valuable source of nitrogen for the 

 farmer in the Maritime Provinces, and especially so when freed to a greater degree 



16—11 



