106 



August, 1908. 



GUMS, RESINS, SAPS AND EXUDATIONS. 



PLANTING OF THE NEW SPECIES 

 OF MANIHOT. 



It is reported that the Bahia-Kauts- 

 chuk-Actiengesellschaft has bought over 

 800,000 acres of land in Bahia, on which 

 the "new" Manihots, Hancornia, &c, 

 are already abundant, and intends to 

 plant it all up with the former. 



So far no British Botanic Garden, not 

 even Kew, has been able to obtain any 

 of the new Manihots other than M. dicho- 

 toma (of which one hundred are grow- 

 ing on the Experiment Station at Pera- 

 deniya), and it is useless for people to 

 apply to the Botanic Gardens for them. 

 In any case we could not supply them 

 till they had seeded freely. In a couple 

 of yeavs' time we shall likely be able, for 

 instance, to supply a little Manihot 

 dichotoma, but only a few thousand 

 seed?, not the large quantities people are 

 already asking for. — Ed. 



THE PRESENT CONDITION OF 

 RUBBER CULTURE. 



By Dr. Pehr Olsson-Sepfek. 



(Paper read before the first meeting of 

 the Mexican Rubber Planters' Associ- 

 ation on October 19, ISO 7.) 



At the present moment, on the date 

 of the birth of the Mexican Rubber 

 Planters' Association, it is opportune to 

 review in brief the development and the 

 present condition of the rubber planting 

 industry. 



Universal interest is now manifested 

 in regard to this industry. The rapid 

 increasing demand for rubber, a commo- 

 dity so closely connected with electricity 

 and many other modern inventions, has 

 called forth the question, whether the 

 world's market can be supplied from the 

 natural sources of wild rubber, which 

 hitherto have been sufficient, or whether 

 cultivation has to be resorted to. 



The concensus of opinion is that 

 although there has been a steady growth 

 of the output of the raw rubber, and 

 although the rate of production so far 

 has shown no decline, we are rapidly 

 approaching the narrowing limits of 

 the natural rubber supply. 



It is generally known that in Brazil, 

 from where the largest amount of rubber 

 has been obtained, the rubber collectors 



have to go further and further inland 

 every year for their supply. With the 

 prevailing reckless method of gathering, 

 the rubber trees are gradually being ex- 

 terminated. Naturally the co'stof collect- 

 ing is thus increasing, and it is to be 

 observed that the extraordinary high 

 prices have not greatly stimulated the 

 production. This applies not only to the 

 Amazon valley, but more or less to all 

 countries producing wild rubber. Very 

 little has been done, and very little can 

 be done to stop this destruction of the 

 natural rubber forests- The natives can- 

 not be taught to consider the necessity 

 of saving the trees for a coming year. 

 Their sole object is to obtain as large an 

 amount of rubber as possible for the 

 time being. 



In some rubber-producing countries 

 steps have been taken towards replant- 

 ing the natural rubber forests. Most 

 notable is the decree passed by the Gov- 

 ernment of the Congo Free State on the 

 5th of January, 1899, in which it is regu- 

 lated that :— 



"In all the forests of the territory 

 rubber trees shall be planted every year 

 to a number not less than 150 for every 

 ton of rubber gathered during the 

 same period. The agents of the State 

 in those forests, where the State has 

 the private owners and concessionaries 

 of all the forests where the State has 

 given it up, whether by decrees of 

 October 30th, 1892, or by the granting 

 of special concessions, are expected to 

 form and keep up these plantations 

 conforming to the conditions specified in 

 the present decree." 



Three years later the Congo Govern- 

 ment issued a new decree increasing the 

 number of plants to be replanted per ton 

 of rubber collected. The production on 

 the Amazon and the Congo has so far 

 not given any sign of decline, but it is 

 certain that the natural supply has not 

 increased. We have on the other hand 

 instances where a rapid decline in the 

 output is taking place. 



In Colombia the export of rubber has 

 been diminishing for the last thirty years, 

 and from Lagos a marked decrease is 

 noticeable for the last decade. 



We are thus confronted with the 

 following situation : while the consump- 

 tion ot rubber is increasing at an acceler- 

 ating rate, the natural supply, although 

 enormous, is not augmenting, in spite of 

 the fact that new rubber-producing 

 plants are discovered and new fields are 

 being exploited. 



