Nov.. 1912.] 



W/ieaf and its CuUivalion. 



is less effective than an equivalent amount of phosphoric acid in the 

 form of super])hosphate. The probable explanation of the sui)eriority 

 of superphosphate has already been indicated. It is not likely to dis- 

 place superphosphate in the wheat areas, especially in districts where- 

 the soil has a high lime content. On sour peaty land, however, it will 

 be found a most useful and valuable manure. The application of super- 

 phosphate alone to these latter soils would only aggravate their acidit}'. 

 Basic slag, however, by reason of the lime it contains, tends to correct 

 the acid conditions, and thus acts as a soil amendment as well as a 

 phosphatic manure. Basic slag is extremely valuable in the top- 

 dressing of impoverished pastures. The results of a large number of 

 pasture experiments in Europe indicate that Thomas' phosphate does 

 not always give a greater weight of herbage than super. The grazing- 

 value of the herbage, however, manured with Thomas' phosphate proved 

 superior to that of super. A greater increase in live weight of sheep 

 has been secured from the pastures manured with Thomas' phosphate 



CLOSER VIEW OE NO. 3. SHOWING PEAS EOR EEEDIXG OFF. 



than those treated with super. The rate of application to wheat land.s 

 is similar to that of superphosphate. 



BONEOrST. 



Bone consists of an organic and an inorganic portion. The organic 

 portion comprises about 40 per cent, of the raw bone, and consists of 

 (o) ossein or bone cartilage, which is very rich in nitrogen; and (&) 

 fat. The inorganic portion, comprising about 60 per cent, of the 

 raw bone, consists principally of tricalcic phosphate (phosphate of 

 lime). 



Hence, the fertilizing principal constituents of raw bones are 

 organic nitrogen and phosphate of lime. 



The presence of fat is, however, highly objectionable, for. in addi- 

 tion to being useless as plant food, it prevents the bones from being 

 finely ground, and also protects the fertilizing ingredients from being 



