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THE GROWTH OF MANICOBA RUBBER TREES 

 IN THE MALAY PENINSULA. 



During December 1908 a quantity of seeds of Manihot dichoioma, 

 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 January 

 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 bmsiliensis ( 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 IOO inches I believe. At the present moment 

 the seedlings are about 10 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. 



