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original remarks. In the original discussion the advantages and 

 disadvantages of "close planting and thinning-out" were briefly 

 given, and the pros and cons of other possible systems require to 

 be dealt with. 



In the planting of Para rubber there are approximately five 

 systems which may be mentioned : — 



1. Close planting — permanent; 



2. Close planting and thinning-out ; 



3. Wide planting — permanent ; 



4. Wide planting with catch and inter crops ; 



5. Interplanting with herbaceous and ar jorescent plants. 



WHAT IS CLOSE PLANTING ? 



To define close planting is a difficult matter, and though actual 

 figures may be quoted, they are subject to modification according 

 to the physical and chemical properties of the soil, and the nature 

 of the climate in which it is proposed to grow the plants. The 

 term — close planting — admittedly implies the planting of the trees 

 at a distance which is not sufficient to allow of the full develop- 

 ment of all parts of the plants ; the latter is determined by the 

 natural vitality of the plants and the nature of the soil and 

 climate. Medium-distance planting in a poor cabook soil, or in a 

 washed out clay above 2,500 feet in Ceylon, would be regarded 

 as close planting in a rich alluvial soil in the low country of the 

 same island. The trees should be planted at such a distance that 

 they will rapidly develop and take possession of the whole of the 

 soil ; their development is controlled by the amount of food 

 which the soil supplies, and it is generally conceded that the 

 better the soil, the more forcing the climate, the greater must be 

 the distance allowed. A typical case is to be seen at the Experi- 

 ment Station, Peradeniya, where some four-year old trees, all 

 planted 15 feet apart, have overlapped their branches on the flat 

 land, but on the upper part of the hill the spread of the branches 

 is hardly a yard on either side ; by the time the latter have taken 

 possession of the soil the former will require considerable thinning 

 out. It has been argued that if the soil is poorer the trees should' 

 be planted at wider distances in order to allow a larger area 

 from which the plants can obtain food ; this is a contention that 

 loses sight of the necessity of quickly placing the plants in' 

 possession of all the soil. 



Disregarding the differences in quality of alluvial, cabook, 

 swampy forest, and chena land, from sea-level up to 3,000 feet 

 in Ceylon, and the allowances to be made accordingly, it may be- 

 generally stated that on the soil similar to that at Peradeniya, a 

 distance of ten feet apart, or less, for trees of Hevea brasiliensis, 

 may be designated as close planting, one of fifteen feet apart as 

 medium distance, and one of twenty feet apart or over as wide 

 planting. These distances are subject to modification according 

 to local conditions, and are here given only to provide a basis for 

 comparison. 



The advantages of close planting are that there is a larger 

 number of trees on a given acreage ; (2) the ground is better 



