THE MANURING OF THE CANE. 



stone pits and are continually repumped over the heap of manure ; the object 

 of this is to rot the manure and at the same time to fix any volatile ammonia 

 given off. In from six to twelve months the manure is considered sufficiently 

 rotten to place on the fields, where it is applied at the rate of from ten to 

 twenty tons per acre to plant canes only, generally at an age of three months ; 

 or occasionally the cane holes are filled with the manure and the tops planted 

 on it. 



The amount of manure made per animal per year is from fifteen to twenty 

 tons where bedding is used, and where the dry dung only is collected, from 

 two to three tons. 



It is very often the case that manure making is forced, that is to say, 

 more straw than necessary to absorb the urine and contribute to the comfort of 

 the animal is brought in as bedding; the false economy of this proceeding is 

 apparent, but its practice is not uncommon. 



The composition of the manure varies within considerable limits ; where 

 a reasonable amount of bedding has been used, the percentage of nitrogen 

 generally, in the writer's experience, lies between *6 per cent, and *8 per cent., 

 falling to '3 per cent, to *5 per cent, where an excess of trash has been brought 

 to the stables or pens ; the potash and phosphoric acid do not seem to show any 

 variation dependent on the amount of bedding used, both lying between the 

 values *2 per cent, to *7 per cent. ; these figures refer to manure with from 

 70 per cent, to 80 per cent, of moisture. 



The expense of making pen manure is very considerable ; the cost in 

 Mauritius varies from two to five shillings per ton, a portion of which expense 

 would be incurred in any case; the carting and application costs about one 

 shilling per ton, making the total outlay from three to six shillings per ton. 

 This expense is very considerable, and in general it may be said that where 

 stock is kept on the estate it will pay to carefully conserve their excreta, but 

 it will not pay to keep animals to make manure, or to force the production 

 beyond its natural limits. 



With the general increase in the size of estates and the consequent neces- 

 sity for mechanical traction, pen manure is losing its importance, and its place 

 is being taken by artificial fertilizers. The fertility of soils in districts, such as 

 Barbados and Mauritius, over many generations is, the writer believes, to be 

 largely attributed to the extensive and well ordered use of the pen manure 

 manufactured on the estates. The modern tendency is to grow crops with the 

 aid of irrigation and of the more concentrated artificial manures, and it largely 

 becomes a question of the cost of the labour required to make and to apply the 

 pen manure compared with that required for the purchase and application of 

 the artificial manure. It is not yet known what will be the final effect on the 

 soil in several generations of the modern practice. 



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