170 SYLVICULTURE IN THE TROPICS K .n 



when these have to be planted above the ground-level, 

 on mounds, in places which are considered too moist 

 for planting at ground-level. In planting districts, the 

 usual size of the holes for average-sized seedlings is 

 18 in. x 18 in. x 18 in. (45 cm. x 45 cm. x 45 cm.) ; but 

 it will depend on the size of the transplants and also 

 whether, as in arid localities, they have to be planted 

 at a level lower than that of the surrounding around. 

 When digging the holes the soil should be taken out, 

 and after stones and roots have been rejected it should 

 be heaped up alongside the mouth of the hole to be 

 well aired before the plants are put in. 



In overmoist soil it may be necessary to do some 

 ridging by digging out trenches and heaping up the 

 spoil earth between them. On these ridges seed is 

 sown or plants are put in. For arid soils trenches can 

 also be prepared. It is usual to leave a margin between 

 the mouth of the trench and the spoil earth in places 

 where heavy downpours are likely to occur, which might 

 drown any seedlings growing at the bottom. Seed is 

 then put in at the bottom of the trench, and more 

 seed on the margin on the brim to provide for all 

 emergencies. 



