208 SYLVICULTURE IN THE TROPICS PT . 



ii 



crown. A too narrow crown has the drawback of not 

 beinsf able to bear much seed. 



As regards the preparation of the soil for the recep- 

 tion of seed, in order that the latter may be offered the 

 best conditions for germinating, and the seedlings for 

 establishing themselves, the gradual opening of the leaf- 

 canopy may become necessary to effect this. 



If the layer of humus and partly decomposed 

 vegetable debris is so thick that the rootlets of the 

 germinating seedling cannot reach the mineral soil 

 within a short time after germination, it is necessary to 

 let in direct sunlight and to admit the free circulation of 

 air in order to reduce this upper layer to a favourable 

 condition for germination and development of the young 

 seedling. This is done by opening the leaf-canopy to 

 the degree which is required, and this degree will be 

 attained more or less quickly according to the nature of 

 this top layer and to the locality ; viz. quicker and 

 heavier cutting is required where decomposition is slow, 

 and lighter where enemies to the young seedlings in the 

 shape of weeds and creepers would also be encouraged. 



On soils which have no covering of vegetable debris, 

 such as are very frequently found in the Tropics, and 

 where the intense sunlight penetrates through the 

 densest leaf-canopy and reaches the soil, preparatory- 

 fellings would probably not improve the latter, and they 

 must be restricted to what is necessary for training the 

 seed-bearers to stand isolation and their crowns to bear 

 a good crop of seed. Where the leaf-canopy is already 

 open, these fellings will not be necessary. 



The best time for making these fellings is generally 

 shortly after the trees have reached their maximum 

 height. They are then in their fullest vigour. It 

 happens, however, that at that time they are often still 

 far from having reached exploitability, and the fellings 

 have to be deferred till later when they are no longer in 

 the very best condition for producing the highest quality 

 of seed. Care should be taken, therefore, to select for 

 retention the finest and soundest of the trees. In a 



