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countries because the cane, generally, contains a high percentage of 

 fibre. The actual damage wrought by the borer is not so much the 

 hole made in the cane as the deteriorating effect on the surrounding 

 tissues which may cause a considerable loss of sugar. The natural sap 

 flow is impaired and the cane can not make so vigorous a growth. 

 Analyses of the affected and unaffected parts of cane have been made. 

 The results showed that the affected tissue contained only 9 \ % sugar, 

 while the healthy tissue contained 14 \ ( f . The proportion of affected 

 tissue, however, is usually small. 



Controlling the borer. In the sugar world a number of remedies 

 have been tried with more or less success. Parasites have been found 

 that are said to prey on certain species of borer. Stripping the cane 

 is advised; cutting the young borer out of the cane; cutting off the 

 young shoot containing the borer; planting the cane at certain sea- 

 sons; killing all weeds on which the borer lives; flooding, and varying 

 the methods of cultivation and irrigation. 



A combined war against the borer, systematically carried on, is 

 probably the only sure means of getting rid of them whatever methods 

 or means may be used, and can be most successfully and economi- 

 cally effected under the direction of a trained entomologist who 

 understands their life history and local habits. Investigation for the 

 control of the borer should receive the same attention that the 

 improvement of the soil or fabrication does. 



Burning the trash in the field is a partial control of the borer. 

 Certain canes are more resistant than others. The stronger any plant 

 is the better it will resist pests, and for this reason it is best to select 

 for planting, canes with few borer holes. The laboratory at Cartavio 

 keeps an account of the average number of borer holes in the cane 

 per section; in this way an idea is obtained of the increase or decrease 

 of the borer, and a standard set for the selection of cane for 

 planting. 



The borer may be spread by planting infested cane, by hauling cane 

 from an infested district to the factory, and by laborers carelessly 

 throwing a cane containing borers into a field. 



