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THE METHODS OF TAPPING CULTIVATED CASTILLOA TREES 

 IN TRINIDAD AND THE YIELD OF RUBBER THEREFROM. 



By Professor P. CARMODY, F.I.C., F.C.S., 

 Director of Agriculture, Trinidad. 



The method most in favour in Trinidad and Tobago for the 

 tapping of Castilloa trees requires no lengthy description. The 

 implements used are a chisel with a specially thin cutting edge 

 about ij in. wide, and a wooden mallet. Every other method 

 has been tried, including paring and puncturing. 



Cuts are made along the trunk about 12 in. apart vertically. 

 Other series of cuts at about 4 in. to the right and left are 

 made, and these are continued right round or half round the 

 tree as high as can be reached on foot or on ladders. 



The chisel is pointed slightly upwards so that the bark on 

 the upper edge of the cut may protrude slightly over the lower 

 edge, and prevent the entrance of rain. Clean cuts should be 

 made, and each cut should slope slightly downwards from the 

 horizontal to facilitate the collection of the latex. The proper 

 depth of the cut is easily ascertained after a short experience. 



It depends on the condition of the trees, and the length of 

 the intervals between the tappings, whether the latex will flow 

 from, or coagulate on, the cuts. If it coagulates on the cuts, 

 the best course is to make a ball of the rubber direct from the 

 tree, stretching the rubber as much as its strength will allow. 

 This stretching appears to improve the rubber. 



The latex when plentiful may be collected in cups, or in any 

 other convenient receptacles, and the rubber immediately 

 separated from it in a centrifugal machine, or more slowly by 

 creaming and setting in shallow trays with porous cloth 

 bottoms. Coagulation may be hastened by the addition of 

 diluted acetic or sulphuric acid, or an aqueous extract of the 

 " moon " vine (Ipomcea bon&'-nox). 



In Trinidad and Tobago Castilloa has not been grown as a 

 separate cultivation. It was recommended some thirty years 

 ago as a shade tree for cacao, and it has been tried for that 

 purpose only over small areas. Under these conditions it has 

 not given, and could not be expected to give, the best results; 

 and the yield of rubber from our trees may be considerably 

 less than that from trees grown under different conditions. 

 The best results that have been obtained in Tobago from young 

 trees tapped for the first time to a height of 20 ft. for half the 

 girth of the tree are for an average of ten trees 10*8 oz., and for 

 288 trees a little over 5 oz. for a single tapping, and 3*4 oz. for 

 a second tapping four months later. 



