THE CULTIVATION OF MANIHOT GLAZIOVII IN 

 UGANDA. 



By SAMUEL SIMPSON, B.Sc. 

 Director of Agriculture, Uganda. 



FOR more than a dozen years Ceara rubber has been 

 cultivated in Uganda, where it grows exceedingly well, 

 and was being generally planted up to a short time ago. 

 The growth is rapid, the average girth being from 19 to 

 .20 in., and the trees thus ready for tapping, when 3 years 

 old. 



On the Government Plantation, Kampala, experimental 

 tapping was carried out last year. The trees, which were 

 3 years old, were arranged in groups containing twenty 

 each, the average girth of the trees in the various groups 

 varying between 15 and 20 in. The system of tapping 

 was the half herring-bone, paring, and pricking. 



The following results were obtained : 



Number of trees Number of times Total yield of dry 



in group tapped rubber in ounces 



20 10 6 



20 

 20 

 20 



2O 



12 



13 ...... 7* 



14 ... 10 

 90 ... ... - 45 



These figures show that to get 2j oz. of dry rubber 

 per tree no fewer than 90 tappings had to be made, and 

 also that the yield obtained from the trees was in prac- 

 tically direct proportion to the number of tappings. 



In July, 1913, eighty trees were taken and tapped on 

 alternate days forty each day and the latex allowed to 

 coagulate naturally. The trees had an average girth of 

 1978 in., and the average yield of dry rubber per tree 

 was o'43 oz. after nine tappings. 



In August, 1913, forty-tree trees, having an average 

 girth of 19 in., gave a total yield of 19J oz. of dry rubber 

 in eleven tappings, or 0*45 oz. per tree. 



