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stay did not permit of further infection experiments being made with 

 the various spores referred to while the evidence from these experi- 

 ments as far as they go points strongly to the parasitic nature of the 

 fungus found in the diseased bark, nevertheless, the point has not, 

 been proved so conclusively and so satisfactorily as in the case of the 

 " brown rot" fungus of the cacao pod. 



There is every probability that this disease is identical with the 

 " canker" disease of the cacao tree in Ceylon and Trinidad which is 

 caused by a fungus of the genus Nectria. There is little doubt that 

 it is the cause of death of a good many cacao trees in Grenada which 

 are popularly supposed to die on account of their tap roots having 

 struck "tiff" or a flat stone. I was unable to find anyone who had 

 verified these alleged causes by actual excavation and, in the case 

 where a tree— attacked by the "canker" disease was dug up for my 

 benefit, nothing of the kind was found and the root system was quite 

 healthy. 



Several trees suffering from this disease were found to be attacked 

 by white ants. On careful examination, however, it was found that 

 in each case the ants were followers of the fungus disease and did not 

 attack the healthy wood. A similar state of things has been reported 

 from Ceylon. 



Remedial Measures. — The group of fungi to which this form in all 

 probability belongs are wound-parasites and gain accsss to their hosts 

 by means of spores which germinate on wounded surfaces. Fortu- 

 nately, the suitable remedial measures are extremely simple and easy 

 to carry out. 



1. All wounds made in pruning and in removing beetle grubs 

 should be tarred as mentioned above. 



2. All dead trees killed by the "canker" disease should be cut down 

 at the ground and burnt along with all the dead wood found in the 

 cacao plantations. 



3. 'lhe diseased bark of the "bleeding" patches should be cut out 

 as soon as noticed Since the roots of the fungus are often found in 

 the apparerj ly healthy bark surrounding the diseased tissue it is 

 necessary to cut out the claret coloured bark and about an inch of the 

 surrounding apparently healthy bark as well When the disease has 

 reached the young wood care should be taken to cut out any discol- 

 oured wood that may be noted. Lhe wounds should be tarred over, 

 and the diseased bark carefully collected in a sack or tin and burnt. 

 The cutlasses or knives used in this work should not be used for prun- 

 ing other cacao trees uutil they have been thoroughly washed and 

 cleaned. In order to enlist, the assistance of the estate workmen in 

 this treatment, a small reward might be given for every tree dis- 

 covered to be suffering from this disease. 



4. In cases when the disease is established to such an extent that 

 cutting out the diseased bark would not be likely to save the tree, it 

 shouid be cut down at some distance below the diseased bark and re- 

 placed if possible by a new sucker. When, however, the disease is 

 nearly on a level with the ground this is impossible and the best way 

 to remove the tree at on^e and replace it by a fresh one. All trees cut 

 down in this way should be burnt immediately. 



The above remedies, if adopted, will I consider keep this disease 



