154 



THE CEARA RUBBER TREE 



1 lb. 14 J oz. was biscuit rubber. The yield per tree was 

 therefore 1"8S oz. for fifteen tappings extending over one 

 month, which must be regarded as very satisfactory con- 

 sidering the age of the trees. It was noticed that some 

 of the trees gave much higher yields of rubber than others. 



The results obtained with this paring and pricking 

 process are very promising, but further experiments ex- 

 tending over a longer period will be required before a 

 final opmion can be formed. Fyife states that in re- 

 tapping a thin paring should be cut from the lower edge 

 of the incision and the latex liberated with a very fine 

 pricker. The tapping is not detrimental to the trees 

 if it is carefully performed, none of those operated upon 

 having died, and the bark is renewed rapidly. The 

 advantage of the method is that it gives a larger yield 

 of rubber, which moreover can be easily prepared in 

 biscuit form instead of being obtained as scrap. 



(5) This method of paring and pricking was subse- 

 quently tried with young Ceara trees at the Government 

 Plantation at Kampala. Half- herringbone incisions 

 extending over half the circumference were made to a 

 height of 4 or 5 ft. and the cuts were reopened on alter- 

 nate days. The following table summarises the results 

 of the experiments : 



The tapped trees showed no signs of injiu-y and after 

 the experiments they grew quite as vigorously as trees 

 which had not been tapped. 



Portuguese East Africa. — Tapping experiments on 

 Ceara trees growing in Portuguese East Africa were con- 

 ducted by Johnson (sec BiiUetin of the Imperial Institute, 

 vol. V. 1907, p. 401). 



One hundred and ton trees, seven to nine years old, 

 were selected for the purpose, and were found to have 

 an average girth of 29-6 in., the largest measuring 44-5 in_ 



