December, 1912,] 



433 



The application of manures to rubber trees is followed by a more rapid 

 growth of all parts of the plant, the bark included. Now the " bark is 

 the mother of rubber." The greater the weight of bark the larger the 

 number of latex tubes, and therefore the greater the weight of rubber.* 

 You cannot have the bark of healthy Hevea Brasiliensis, Manihot 

 Glaziovii. Castilloa elastica, Ficus elastica or Funtumia elaslica trees 

 without latex. Latex is present in the bark of healthy trees and if re- 

 moved from any particular part it soon accumulates until approximately 

 the old equilibrium is re-established in the affected area. If more bark 

 is formed as the result of manuring, it will assuredly become filled with 

 latex like the renewed bark which takes the place of that removed 

 during paring operations. 



Need of Experiments. 



It being taken for granted that manuring does stimulate the growth 

 of the plant and that a total increase in plant tissues means an increase 

 in the rubber content, it now remains to prove that an increased rate of 

 growth is desirable. It is asserted by many that there is a maximum 

 rate of growth in all plants which it is not desirable to exceed. It is com- 

 mon knowledge that manures can "force" plants and that the resulting 

 specimens may be really weak and unable to stand well against the 

 ordinary variations of environment or the attacks of pests and diseases. 



Viewing the rubber planting industry in its widest sense, there is no 

 doubt as to the necessity of manuring and tillage. Estates have been 

 planted on poor soil, at high altitude and in uncongenial climates ; others 

 have been planted at close distances and after thinning out the remain- 

 ing trees present a backward appearance. Numerous estates are not 

 able to tap the renewed bark because it has not grown so rapidly as 

 was expected, and monkey tapping, V tapping on restricted areas and 

 other methods have been resorted to. There would be no difficulty in 

 quoting a large number of estates possessing trees which badly require 

 either a good rest or extra food to stimulate the rate of growth. 



Those proprietors who admit the necessity of manure are sometimes 

 sorely perplexed because there is very little information of a reliable 

 character respecting the components and quantities of the different in- 

 gredients which should be applied. It is true that experiments have been 

 made in Hawaii, Sumatra, Ceylon, and Malaya, but in no case can we con= 

 fidently accept the results for general guidance. 



DRESSING OP PRUNING CUTS. 



Mr. W. Cradwick writing to the Journal of the Jamaica Agricultural 

 Society on the tarring of wounds when pruning trees, observes that 

 the operation is often looked upon as the most simple one connected with 

 the art of pruning and is usually relegated to a boy or the most careless 

 and ignorant of a band of primers. Tar is often plastered on to such an 

 extent that it runs from the wound tarred, down the stem of the tree to 

 the ground, wasting the tar and in the case of young trees doing them 

 considerable harm. Tarring of wounds should be done by experienced 

 men only. To tar a wound avoid fancy experiments and troublesome 

 mixtures. Rub a little coal tar thoroughly into a wound so that even the 

 most minute crack will be filled up, the thinnest form of tar being applied. 

 If the tar is hot so much the better but this is not absolutely necessary, 

 though it should be rubbed in hard. The best brush is a piece of the half- 

 dry coconut husk. 



* We believe this has not yet been demonstrated . Ed. T.A, 



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