and Magazine of the Ceylon Agricultural Society.— August, 1911. 185 



ground ; if the same did not rebound well 

 there was evidently a fraud by means of 

 mealy or gummy products without any value. 

 French and Belgiau Congo were the African 

 colonies which were the richest as to rubber 

 species, and it was also in those countries that 

 the greatest variety was encountered in the pro- 

 cesses of gathering and coagulating the latex. 

 Growth of Para. 



Mr. H. A. Wickham— read a paper on "The 

 Para Rubber Trees in the East," in which he 

 dealt with the danger of too close planting, as 

 tending to arrest growth, impair vitality and 

 set up a struggle for existence which consti- 

 tuted a serious menace for the future. Clean 

 weeding he described as "clean scrapine," 

 which exposed the soil to the sun and rain, the 

 latter being carried away. The root system 

 consequently suffered from exposure. Syste- 

 matised mulching was better than clean weed- 

 ing. As regarded tapping, ho advocated " inci- 

 sion " as against "excision. It was not at all 

 necessary to pare away growing tissue. 



In the course of discussion Mr. Bambek — 

 pointed out that, as regarded close planting, 

 they had to look at it from a financial point of 

 view. He was in favour of retaining the soil 

 around the tree. 



Mr. Fox — characterised clean weeding as a 

 " fetish," and Mr. Wycherley was in favour of 

 close planting, as he did not think it had the 

 bad effects which were attributed to it. 



Mr. Wickham— in his reply— emphasised hia 

 previous points. 



Dr. E. De Wildeman — read a paper, the sub- 

 ject beine 



"AFRICAN RUBBER VINES : THEIR CULTIVATION 

 AND WORKING." 



In the course of his address Dr.Wilderman said 

 that from the researches of various botanical ex- 

 plorers we knew that numerous rubber-bearing 

 vines or creepers existed in tropical Africa, 

 which vines have for some years supplied almost 

 all the rubber for the African trade. Their 

 distribution over the African continent was 

 very wide. Broadly speaking, the rubber vine 

 area extended from Senegambia and the Upper 

 Nile to the south of Angola, of Ehodesia, and 

 Mozambique, even to the Cape district. Not- 

 withstanding many favourable opinions, the 

 various species of vines, although undoubtedly 

 producers, had neither been cultivated nor 

 worked as they should be. Nearly all the 

 African rubber brought over to Europe, espe- 

 cially from the Congo, had come from wild- 

 growing plants, and very often the native, 

 through an intensive and altogether irrational 

 harvesting, had caused a reduction in the num- 

 ber of producing plants, if not their disap- 

 pearance. At first cultivation consisted of 

 seeding in nurseries and setting out the plants 

 afterwards in the woods, or else direct seeding 

 in the woods or in the forest roads. It was 

 soon found that, while vines could be grown 

 from the seed, they attained in the forest in- 

 significant dimenfions. To obtain plants as 

 vigorous as the vines worked in the forest 

 by the native, under the conditions there ex- 

 isting, one would have had to wait a consider- 

 able number of y6ars. 



The result of this was naturally unfavourable 

 to the progress in the cultivation of vines, their 

 great fault in the eyes of the Government being 

 the slowness of their growth. But one of the 

 conditions of the experiment had not been 

 thought of — the biology of the plant had been 

 altogether overlooked. To allow a plant to 

 develop normally one must give it not only the 

 necessary soluble mineral elements through the 

 soil, it must also absorb through its leaves the 

 carbon from the carbonic anhydride contained 

 in the air. What did a plant require to effect 

 this decomposition ? Light and chlorophyll. By 

 planting vines under the shado of trees they 

 were placed in very unfavourable conditions for 

 accomplishing this assimilation, because they 

 were deprived of sunlight. The vines now 

 being exploited in the tropical forests had devel- 

 oped very well, because they grew up with 

 the forest, exposing their leaves, flowers, 

 and fruits to the sun together with the 

 trees. Everybody now agreed that the me- 

 thods of gathering latex used by the natives 

 of Africa were more or less defective. One sel- 

 dom saw a case where the native extracted 

 all the rubber contained in the vine. The first 

 method consisted in pulling the vines off their 

 props, to get at them easily. The native then 

 very often spreads the stems more or less parallel 

 to the ground, keeping them a certain distance 

 from the soil by means of supports. Afterwards 

 he made incisions in the stems at regular 

 distances, and gathered up the latex which 

 flowed out. 



It was asserted that the greater number, if 

 not all, the plants thus treated died in the un- 

 derbush, not only because of the unfavourable 

 conditions for vegetation, but also because the 

 wounds caused in the pulling down and tapping 

 would become infected with plant diseases, 

 against which not the slightest precaution had 

 been taken. The reply might be made that the 

 plant would throw out new shoots. That was 

 possible, but they would be few in number, 

 because the vine would first try to heal 

 its wounds and to fight the microbes 

 that invaded them, and would nearly al- 

 ways exhaust itself in futile efforts. Another 

 method used by the natives consisted in 

 tapping the vines without pulling them down. 

 Cutting constituted the third method, which 

 was a modification of the first one, and was 

 often followed up by threshing. The native 

 pulled the vine off its prop, then instead of tap- 

 ping it it was cut in pieces, aud he gathered the 

 latex which flowed from the ends. This method 

 at first sight looked destructive, but when care- 

 fully examined proved to be superior to all 

 others. Indeed, this was the method of the 

 future, but some modifications had to be made 

 to certain details of its application. What now 

 were the objections that could be raised against 

 this method ? Only one of importance : The 

 latex did not all flow out of the pieces of the 

 vine ; therefore a considerable quantity of the 

 rubber was lost. It had also been objected that 

 the native killed the vino by this barbarous 

 process. 



At the session's opening on Wednesday there 

 was a continuance of the discussion on Mr. 

 Fyffe's paper on 



24 



