Diseases 241 



of sugar which the tissues contain. The 

 symptoms, we are told, vary according to the 

 age and nature of the trees attacked. In 

 general, cracks appear in the bark, from which 

 a brown viscid liquid oozes that soon turns 

 black and leaves a dark stain on the bark. 

 On cutting away the cortex near the crack, it 

 is often found that the tissue has decayed and 

 become soft and watery. In some cases the 

 outer layer of tissue falls off, leaving a hole 

 filled with fibres ; in other cases spiral 

 cylindrical hollows are formed, running up and 

 down the stem ; while in extreme cases the 

 whole tree may be rendered hollow to within 

 2 ft. or 3 ft. of the terminal bud. This may 

 occur only when a few bleeding patches are 

 visible externally. The disease does not 

 necessarily cause the death of the trees, and 

 its effect on the crop is usually small, at any 

 rate for a time. Its importance lies principally 

 in the fact that trees weakened by the presence 

 of the hollow spaces in their stems are liable 

 to be broken off in a strong wind. It is much 

 more prevalent in wet than in dry weather. 

 Pamphlet No. 70 then suggests as a remedy 

 to cut out the infected tissues and burn all 

 chips. This is best done with a chisel and 

 mallet. Wounds slanting upwards, we are 

 told, should be made in order that water may 

 run off them. When the diseased portions 

 have been cut out, the surfaces of the tissues 

 should be carefully burnt with a torch to dry 



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