August, 1909.] 



103 



Saps and Exudations, 



age production of 2 or 3 pounds per 

 tree over considerable areas, taking 

 young and old trees together. In addi- 

 tion to the data on this subject on 

 another page of this issue, it may be 

 noted that Mr. J. B. Carruthers esti- 

 mates that all the rubber trees tapped 

 in Malaya in 1907 yielded an average 

 of 1 pound 12 ounces. The trees included 

 in Perak alone yielded 2 pounds 1 ounce, 

 and those in Negri Sembilan 2 pounds 

 7 ounces. These are not exceptional 

 yields, but the figures relate to upwards 

 of 1,300,000 trees. 



We might pause here to consider the 

 ultimate rubber production of Malaya, 

 where, according to Mr. Carruthers' 

 figures, the rubber planted to date — 

 nearly all within three years — covers 

 about 280 square miles of territory. In 

 this great forest formed by the hand 

 of man it is estimated that there are 

 97,558,440 rubber trees, planted generally 

 at what is intended to be permanent 

 distances apart. If all these eventually 

 should give a yearly average of 2 

 pounds, the result would vastly exceed 

 the world's present total production of 

 rubber. In none of these estimates, by 

 the way, is any account taken of Ceylon 

 or the Dutch Indies, or of any part of 

 America or Africa where rubber has 

 been planted. 



But our interest at this time is con- 

 fined to the present yield of plantation 

 rubber, and it appears abundantly estab- 

 lished that the yield is ample for 

 present profits on a scale beyond what 

 is usual in most branches of agriculture. 

 We must not leave the subject, however, 

 without pointing out that all the figures 

 used in this connection bear solely upon 

 the cultivation of one rubber species — 

 Hevea— in one part of the world. The 

 study of other species, and under other 

 conditions, remains to be carried to a 

 practical conclusion. 



CEARA RUBBER (MANIHOT 

 GLAZIOVII). 



By H. Powell. 



(Prom the Agricultural Journal, British 

 East Africa, I. 3, April, 1, 1908.) 



•Ceara or scrap rubber of commerce is 

 produced by a small tree growing to a 

 height of about 30 to 35 feet and attain- 

 ing a stem, when fully developed, of a 

 foot or more in diameter. The tree 

 belongs to the natural order Euphor- 

 biacese, and its natural habitat is said to 

 be the Province of Rio Janerio, though 

 it is now common in many tropical 

 countries. 



Well-grown trees are established at 

 Mombasa and Rabai, and cultivation of 

 Ceara rubber has during the past year 

 or two been taken up on a commercial 

 scale at Voi and Kibwezt. In the 

 country around Malindi, also at Meritini 

 and higher up the railway in the Mazeras 

 district fairly large numbers of Ceara 

 seedlings have recently been planted, and 

 a much larger increase in this direction 

 is anticipated during 1908, the demand 

 for Ceara seed through the Agricultural 

 Department being considerable. 



A large plot of Ceara rubber trees at 

 Meritini Experiment Station, Rabai 

 district, is in vigorous health, the most 

 advanced trees — about 20 months old — 

 having already yielded good samples of 

 rubber. 



Several acres are being established at 

 the Mazeras farm where the soil and 

 general climatic conditions are seemingly 

 eminently adapted for Ceara ; the condi- 

 tions existing at this place are typical 

 of much of the surrounding country. 



So far as can be ascertained the first 

 Ceara trees in British East Africa were 

 planted at the Mission Station, Rabai, 

 whence the trees in the grounds or 

 Mombasa Club were obtained by Mr. D. 

 J. Wilson about nine years ago. 



In 1883 Ceara rubber plants were intro- 

 duced to Zanzibar from the Royal Gar- 

 dens, Kew, and about 1892 or 1893 Baron 

 Von St. Paul Ilaira obtained seed from 

 another source and raised plants at 

 Tanga, which were given by him to Mr. 

 Koehler of Lewa in the Pangani district, 

 and from these the extensive Ceara rub- 

 ber industry in German East Africa has 

 been mostly established. 



The seed now being itn ported into Brit- 

 ish East Africa is from the Tanga 

 district. 



Propagation.— This is usually effected 

 by seeds which should be at least a year 

 old from the time they fall from trees, 

 and the latter should be from 3 to 4 

 years old, as seed collected from young 

 trees do not produce such vigorous plants 

 as from those of the age given. 



If fresh seed is planted, i.e., seed newly 

 collected, germination is very slow, if 

 at all, whereas seed one or two years 

 old germinate readily and well and give 

 good results. 



Soaking the Seed.— Some growers 

 place the seed in water for varying 

 lengths of time, and others pour boiling 

 water over the seed with a view to soften- 

 ing the shell or seed coat. In connection 

 with this subject Mr. Gustav Eismann 

 of Hale, Niussi, near Tanga, carried out 

 a series of experiments by soaking th e 

 seed in water from a few hours up to a 



