cH.Yin REGENERATION BY SEED 219 



and dying trees become the hosts of numbers of 

 destructive insects and fungi, and, in case of a forest 

 fire, feed the flames and add to their intensity. They 

 may even be the cause of repeated forest fires, for 

 sometimes trees which have been set alight will 

 smoulder for months on end, and provide the means of 

 starting other fires later on. In such forests, therefore, 

 it is best to make such operations with a light hand 

 and to pass over the same place oftener. 



Trees grown under the selection method are less 

 likely to give first-class timber than those grown under 

 one of the uniform methods. The forest, as has already 

 been stated, consists of trees of all sizes and ages ; large 

 trees may be standing close to small ones, and part of 

 the bole remaining exposed, the lower branches on the 

 exposed side do not die off but, on the contrary, develop 

 to a large size, and not only is the growth of timber 

 stronger on that side of the bole, thus forming uneven 

 rings of growth and consequently uneven grain and 

 uneven strength in the timber, but large knots are 

 formed which impair its quality. There is also more 

 risk of twisted fibre in the timber, owing to the action 

 of the wind on the exposed portions of the crown. The 

 method also presents a good many difficulties when the 

 forest is a mixed one, largely composed of shade- 

 enduring species, but the most valuable shade-avoiding. 



Nevertheless, owing to the simplicity of the method 

 and to the dangers which are met with from exposure 

 of the soil to a tropical sun, or to tropical downpours, or 

 from invasion of weeds, shrubs, bamboos, etc., this 

 method is practically the only high - forest method 

 which has been employed in the tropical forests of the 

 Old World. In the Indian and Ceylon Government 

 forests, for example, where the exploitable size for 

 timber trees is usually taken at 6 or 7 ft. (180 to 

 210 cm.) in girth, it is calculated how many years it 

 takes for trees of the girth class next below that size 

 (which used to be taken at from 4 ft. 6 in. to 6 or 7 ft, 

 or 135 to 180 or 210 cm. in girth) to reach that girth, 



