CLEAR CUTTING IN HIGH FOREST. 91 



age and height (or nearly so) ; as soon as the branches 

 begin to interlace, the trees form an uninterrupted leaf canopy 

 overhead, which, with advancing years, becomes more and 

 more elevated above the ground, leaving a space below, in 

 which the branchless trunks or boles of the trees tend 

 upwards. 



In a wood of this class the sunlight reaches only the upper 

 parts of the crowns, the result being that height growth and 

 the formation of clear boles are specially favoured. The 

 density of the cover, and with it the diameter growth, depend 

 on the character of the species, the quality of the locality, 

 and the degree of thinning. At the end of the rotation the 

 wood is cleared oft" the area, and the process of formation 

 recommenced. 



h. L'.rferiia/ J)//ni/ers. 



The principal dangers are those of frost, drought, insects 

 and storms. In early youth a wood formed on a cleared area is 

 exposed to all meteoric influences. In winter, and especially 

 in spring and autumn, frost threatens the young plants, if they 

 are at all sensitive to it, and in summer the uninterrupted ex- 

 posure to the sun may dry up the soil and plants ; they may 

 also be seriously injured by a strong growth of weeds. More- 

 over, air currents strike over the area without interference. 

 There can be no doubt that many diseases, which perhaps appear 

 only later on, can be traced as having originated during this 

 period of early exposure. At that time the greater dryness of 

 the soil attracts insects, which concentrate their breeding places 

 in it, while the absence of trees causes insect-destroying birds 

 to be comparatively scarce. 



AVhether woods produced under this system are more sub- 

 ject to damage by storms than woods produced under shelter- 

 woods is doubtful, varying views being held on the subject. 

 On the one hand, trees of even age standing in crowded 

 woods protect each other, but on tlie other hand individually 

 they do not stand as firm as trees grown up in a more free 



