256 
Notes on the Cultivation of Hevea Braziliensis 
(Para-Rubber) and the yield or Rubber crop. 
Para rubber is a crop which, if the plantations in the East are 
carefully tended, might be continued for 60 years. The life of a tree 
or estate may be lengthened or shortened by the treatment accorded, 
but, as will be shown in these notes, the real test of successful 
cultivation in view of prospective crops depends entirely on the 
annual increment of growth of the trees. It is an indisputable fact 
that the ratio of yield increases with the size of a tree, both in respect 
of dry weight of rubber and better latex-producing rubber The 
following statement illustrates both facts:- 
SMALL AND LARGE TREES. 
No of 
Trees 
tapped. 
Aggregate 
girth at 3 ft. 
from ground. 
Number of 
times tapped. 
Fluid ozs. 
of latex. 
1 
! Dry 
weight 
of rubber. 
Ratio of fluid ozs, to ozs. 
avoirdupois, 
j 
Small 
Trees. 
90 
220' 5" 
24 
3511 
37 lbs. 
5H Nov.-Dee. 
120 
276' IOf" 
26 
3433 
43 „ 
4-II Oct.-Nov. 
100 
276' IO£" 
28 
3981 
48 „ 
5 1% Sept. 
310 
774' 2 i" 
26 
10925 
128 „ : 
1 
(Total small trees). 
Large 
Trees. 
150 
743' 4 i" | 
30 
18748 
251 8 
4§ Nov. -Dec. 
It should be pointed out that the large trees have not been 
specially selected and the returns from the same trees were much 
more favourable in 1906, when these 150 trees supplied 15,280 ozs. of 
latex which resulted in 268 lbs. of rubber. For the purpose of this 
comparison, large and small trees were selected which had been tap- 
ped concurrently and the apparent facts must be convincing, viz. — 
310 trees of an average girth of 2-6" furnish more than half (slightly 
over 9/16) of the quantity of latex and only about half the dry weight 
of rubber of 150 trees of an average girth of 4-10", i.e. t the large trees 
were less than half the number of young trees; girth less; latex less 
pro rata ; dry rubber nearly double. 
The difference in the quantity of latex between young and old 
trees of nearly the same aggregate girth is not very large, although 
variable; it is evident, however, that the ratio of caoutchouc to the 
