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THE GROWTH OF MANICOBA RUBBER TREES 
IN THE MALAY PENINSULA. 
During December 1908 a quantity of seeds of Manihot dicho'.oma, 
Ule, and Manihot piauhyenis, Ule, were received at the Botanic Gardens 
Singapore, through the agency of the Royal Botanic Gardens, Kew, 
the Royal Botanic Gardens, Calcutta, and the Forests and Gardens 
Department, Hongkong, for experimental purposes in the Malay 
Peninsula. Part of the seeds or seedlings were given to Planters 
who were anxious to try them on their estates. The remaining seeds 
were sown in Singapore. In the Agricultural Bulletin for /anuary 
of this year ( No. I, Vol.VIII ) I gave a short description and account 
of the cultivation of these Manihots in Brazil and at the same time 
promised to give a report of our trials in a future number of the 
Bulletin. Ten months having now elapsed since then, I am able 
to give an account of their growth during that period. 
On Tebrau estate, Tampoi, Johore, a number of seeds of each 
species were sown in the same seed beds and two months previous to 
seeds of Hevea brasiliensis ( Para ). The soil on which the seed beds 
are formed is light and sandy and the annual rain fall in the district 
is not heavy, about 100 inches I believe. At the present moment 
the seedlings are about io months old. The Manihot seedlings show 
a much more rapid growth than those of Para, the branching tops 
of the former standing clear above the surrounding plants of the 
latter. The biggest plant is now over 15 feet high and 8 inches in 
circumference at 3 feet from the base. 
Early this year a small case of seedlings was despatched from 
the Botanic Gardens, Singapore, to Sengat Estate, Ipoh, Perak, 
and Mr. Lyal Patterson informs me that the growth of his 
plants has been a surprise to him. One plant, he says, is over 
seven feet in height and all the others are well over five feet. 
One plant that was topped is now a fine bushy tree. The soil is also 
of a light sandy nature and the annual rain fall is not heavy. 
The seedlings in the Botanic Gardens, Singapore, show similar 
growth to the above-mentioned cases. The plants vary in height 
from 8 feet to 12 feet with an average girth of 4 inches at 3 feet from 
the ground. The plants branch dichotomously and from very 
regular well-balanced tops. In appearance the two species of Manico- 
bas are very much alike, but are easily recognised by the following 
differences in their leaves 
Manihot dichotoma, leaves three to five lobed, pale green on the 
under surface, with ribs of greenish white, the contrast of the leaf with 
the ribs being sufficiently well marked to enable the species to be 
identified at a glance. Tree said to attain a height of 30 feet and 
more with a diameter of some 2 feet when fully matured. 
Manihot piauhyensis, leaves 3 to 5 partite, ribs on underside of a 
purplish colour, leaf itself being of a darker green than the former. 
Small tree 6-16 feet tall. 
