F. T. Brooks 21 1 



phi nt only about LOO per acre. On many older estates thinning out 

 has reduced the number of trees per acre to 80 or ( .><>. Now that over- 

 crowding is prevented the trees have a better chance of attaining 

 their natural habit of growth, and air and light being freely admitted to 

 all parts of the tree there is less danger of the establishment of disease. 

 Where estates are thinned out it is necessary for the rubber stumps 

 to be removed from well below the surface of the ground, otherwise 

 there will be danger of root troubles later. ' 



The methods of tapping in vogue at present are much more con- 

 servative than those formerly practised and longer periods are allowed 

 for bark renewal, all of which tends to preserve the health and vigour 

 of the trees. Many of the older trees were overtapped during the boom 

 of 1910 and in consequence are poor specimens at the present day. 



On account of the reduction in the number of trees per acre on 

 most estates in comparison with the number formerly customary, 

 each tree is now of more value as a potential or actual latex producer, 

 for in the long run an acre bearing 100 trees will yield more rubber 

 than an acre in which 350 trees remain. An estate containing 80 to 

 90 trees per acre cannot afford to lose many trees through disease, 

 hence the smaller the number of trees per acre the more important 

 does it become to do everything possible to ensure vigour in the trees 

 and, if disease does appear, to treat it as soon as possible. The retention 

 of only 40 trees per acre has been advocated by some authorities but 

 the loss of a few of these trees from disease would cause such a serious 

 reduction in the output of latex that upon this consideration alone it 

 would appear preferable to retain about 80 trees to the acre. 



When trees are killed by disease in plantations more than two or 

 three years old it is usually not worth while to replant vacancies as 

 supplies become crowded out by the older trees unless the vacant 

 areas are extensive. 



It is found advisable on most estates to keep a special coolie gang 

 to deal regularly with pests and diseases, the size of the gang being 

 regulated according to the amount of work to be done. Upon estates 

 affected by Pink Disease the maintenance of a pest gang sufficiently 

 large to go over the whole estate once in three or four weeks is an 

 imperative necessity. European supervision should always be exercised 

 over the treatment of disease although coolies often become remarkably 

 expert in finding unhealthy trees. 



As is only natural, managers of estates sometimes express regret 

 at the cost of the pest gang though many of them realise that money 



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