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The Supplement to the Tropical Agriculturist 



should bo taken up by the roots, is actually 

 poisonous and cannot be used by them at all. In 

 fact, it has much the same effect as sea-water. 



Nothing could be more unsuitable for the 

 Hevea which requires a lot of water and re- 

 quires it good. Plants in soil such as this 

 become weak and very soon succumb to the 

 attacks of fungus. They have no strength to 

 resist any disease. In any case they could 

 never make healthy trees, even if there was no 

 fungus about. In ground of this nature I have 

 recently heard of a mortality of 100 per cent, 

 and that the area planted has had to be en- 

 tirely abandoned. In many parts of the 

 Peninsula there are still left considerable areas 

 of similar soil to this I have described, and 

 planters would do well to avoid this ground 

 entirely for rubber planting. 



H. N. Ridley. 



— Straits Agricultural Bulletin, for Oct. 



RUBBER PLANTING DISTANCES. 



AND FORM, 



To the outsider desirous of taking an intelli- 

 gent interest in his plantation investments, one 

 of the most open questions seems to be the cor- 

 rect planting distances between trees. No two 

 authorities agree on this point and individual 

 planters all seem to have their own ideas. Time 

 will doubtless show whether room for the ulti- 

 mate possible growth should be provided from 

 the outset, or whether a much closer distance 

 should be adopted while the trees are young. 



Apart, however, from planting distance there 

 is the matter of planting form. So far as can 

 be gathered from publicly issued prospectuses 

 and reports, the great majority of estates are 

 planted either on a true rectangular system or 

 on the equivalent diagonal system ; the state- 

 ment being generally that "the trees are planted 

 (say) 16 x 16= (say) 170 to the acre." The standard 

 books on Para rubber contain no reference to 

 any other lay out. 



Is the rectangular system the best to adopt ? 



It allocates to each tree either a square, rec- 

 tangular or a diamond-shaped plot for root and 

 branch extensions, before interference or con- 

 tact with adjoining roots and branches, and it 

 tends to squared fields or blocks with avenues 

 and roads at right angles. 



Of rectangular systems the square is obviously 

 that in which the whole ground area is earliest 

 covered by roots, i.e., brought under contribu- 

 tion. With equal area per tree the other rec- 

 tangular forms with one long and one short axis 

 (e.g. 20 ft. x 10 ft) involve very early interference 

 in one direction and long roots to cover ail 

 the ground in the other direction. 



If it be conceded that the natural, unrestricted, 

 root-and-branch extension is substantially equal 

 in all directions round the trunk, then the area 

 allocated to each tree should be concentric with 

 the trunk, and a series of circles would represent 

 the growth at any time prior to contact. After 

 contact the circles merge into hexagons. 



It is submitted that the hexagon is the true 

 form of ground area which should be given to 

 each tree for the best possible results in the way 

 of rapid growth and ultimate development. 



With any given minimum distance between 

 trees— fixing the period of unrestricted root and 

 branch extension before the first check of inter- 

 ference — a block planted on the hexagonal sys- 

 tem will carry 15 per cent more trees than if 

 planted on the rectangular or staggered system 

 thus : — 



Planting Distance. Square Lay-out. Hexagonal Lay-out* 

 18 ft. 134 154 trees per acre. 



20 ft. 109 126 trees per acre. 



22 ft. 90 103 trees per acre, 



24 ft. 76 87 trees per acre. 



The hexagonal system leads to avenues in three 

 directions and facilitates working a block of any 

 size to a local centre if decentralisation be de- 

 sired. It is particularly easy to lay out. 



It is not suggested that this discussion is 

 original because the present writer knows of 

 one, but only one, rubber plantation where the 

 system has been adopted. 



ROBERT THOMPSON. 

 25th September, 1909. 

 — India- Rubber Journal, October 4. 



THE QUALITY OF CEYLON RUBBER. 



A German Chemist's Opinion. 

 Mr. Wm. Pahl, chemist, Judge of Commer- 

 cial Affairs, and proprietor of the Dortmund 

 India-rubber Factory, Dortmund, Germany, 

 selected by the German Government to visit 

 rubber-producing countries in the interest of 

 science, in conversation with our contem- 

 porary's representative yesterday, said he had 

 visited estates at Baddegama, Alutgama, Pana- 

 dure, Kalutara, had run up to Peradeniya, and 

 also Kurunegala. It depended on the articles 

 to be made whether manufacturers would prefer 

 biscuit or sheet rubber, but, on the whole, 

 they preferred sheet. The Ceylon quality was 

 splendid, and the industry in the whole East had 

 a great future before it. From a manufacturer's 

 point of view the quality of Ceylon rubber, 

 however, is not as good as the rubber from 

 Brazil. The latex is treated with acetic acid, 

 but he did not think a groat deal of that pro- 

 cess. Probably attention ought to be given to 

 manuring. There was very good soil in Ceylon. 

 He had taken samples, and tests would be made 

 at home. The prices would not remain at the 

 present high figures when more rubber is placed 

 on the market. Next year manufacturers hoped 

 the price will be about 5s. Prices would be 

 fixed in February or March, because at that 

 time the supply from Brazil will be forward. 

 It was expected that there would be!a 10 per cent 

 increase on the previous year's stock, and, 

 naturally, although the price two or three years 

 hence may be 3s to 3s 6d a lb., the market would 

 depend upon the production. 



RUBBER IN BRITISH NORTH BORNEO. 



If Rubber trees continue to give 3 lbs of dry 

 rubber daily, as shown in an extract (in our 

 daily) from the North Borneo Herald, that is 

 the country to grow rubber in ! No wonder 

 the Companies' £1 shares, which, about a year 

 or two ago, were to be had for 13s and 14s, 

 are now selling for £1 5s. 



