102 CHAPTER VI 



generally in the Hawaiian Islands, in Demerara, and in Java where the fields 

 after the cane harvest are turned over to the native Javanese for rice culture. 

 In Mauritius, however, much of the trash is used as bedding for the plantation 

 stock, and thus finds its way back to the soil as pen manure, and a similar 

 routine obtains in the British West Indies. In Cuba it is the almost invariable 

 custom to let the trash rot on the fields, where it remains as a blanket. It 

 thus not only is returned to the soil, but equally acts as a mulch preventing 

 surface evaporation, and to this custom the long-continued fertility of much 

 of the Cuban cane lands is to be attributed. In those districts where the 

 trash is burned off either before cutting or afterwards, it is not ignorance 

 that causes the custom to obtain, but rather lack of labour or absence of 

 means of satisfactorily burying or turning under the very bulky mass of 

 material. 



Apart from the value of the nitrogen, the presence of decaying vegetable 

 matter in the soil has an important bearing on its fertility in regard to the 

 formation of humus and in increasing the water-holding capacity of the soil, 

 and in this connection it may be remarked that those plantations on the 

 island of Hawaii that have made a practice of turning under the trash always 

 suffer less during a drought than do those which habitually burn it off. 



During the period 1901-13 extensive experiments were made on a Hawaiian 

 plantation, in all 109,990 tons of trash being buried. The effect of this 

 procedure is thus described : — ^^ 



" Where two ratoons were formerly the maximum, four are now becoming the 

 rule. The yields, instead of decreasing with each subsequent ratoon, have in- 

 creased. The 1908 crop was the first to have trash left over its entire ratoon area. 

 That and the succeeding crop.= show an average yield of 4' 102 tons of sugai per 

 acre ; the seven preceding crops gave 3* 329 tons of sugar per acre. The 1914 crop 

 to date has yielded 5' 2 tons per acre and is expected to go still higher. While all 

 the credit cannot be given to trash, there is no doubt whatsoever that leaving the 

 trash has been the principal factor." 



The actual operations there followed on a rainfall plantation are described 

 by Larsen^^ : — 



" After the cane is cut the trash is hoed away from the stools into the furrow. 

 This work requires about two men per acre per day and is called " palipali-ing.'" 

 This is followed by offbarring, which consists cf ploughing off or away from the stools. 

 The soil by this operation is thrown against and partly over the trash and assists 

 materially in hastening its decay. A 10, 12, or 14-inch plough is used for offbarring. 

 A revolving knife or sharp coulter is attached to the plough-beam to make a clean 

 cut ahead of the plough. One man with two mules can offbar 2 to 2^ acres per 

 day. After offbarring hoeingis done in the cane lines. In the furrow, that is, between 

 the lines of cane, the weeds in most cases are kept down effectively by the trash. 



Cultivation between the rows begins from one to two months after pali-pali- 

 ing. After two or thiee more hoeings in the cane rows as occasion demands and as 

 many more cultivations the trash will have become so thoroughly broken up and 

 disintegrated that the furrow can be small-ploughed without trouble. A small 8-inch 

 plough is run usually four times through the furrow to loosen up the soil and to mix in 

 the trash. After small-ploughing the cane is hilled. This is done with hoes, ploughs, 

 double mould-boards, or discs. With this operation the rotted and partly rotted 

 trash is thrown toward the cane and is more thoroughly buried and mixed with the 

 soil." 



In certain soils in Demerara the presence of decaying trash has according 

 to Harrison^* a specific function in neutralizing the effect of the large quantity 

 of alkaline soil water there present. On this point he writes : — 



" In experiments in which (i) soil water was allowed to evaporate into the 

 air and (2) caused to evapoiate in an atmosphere consisting almost entirely of free 

 carbon dioxide, it was observed that when the evaporation takes place in air» 



