G ELEMENTS OF SYLVICULTuKE. 



leaves, or from the soil, and intercepts the direct rays 

 of light. Shade, less injurious than cover, is useful 

 only so far as it affords shelter. 



To exploit a forest or crop means to fell it in 

 accordance with the principles of Sylviculture. 



A forest is exploitable when it has attained the 

 maximum of utility for its proprietor. The state of 

 a forest in which this condition has been realised is 

 expressed ty the word exploitability . 



By annual yield is meant the quantity of produce 

 that can be taken out of a forest annually while 

 maintaining the production at a constant figure. 



GENERAL IDEAS. 



CLIMATE. Climate is used in two senses : first) 

 the geographical climate, which depends on the 

 latitude, and secondly, the physical or local climate* 

 which depends chiefly on the situation and aspect of 

 the place in question. The distribution of the 

 various species 'over the face of the earth is the 

 principal result of the first kind of climate ; for the 

 forester it has only a general, though very important, 

 interest. The second, while also influencing the 

 distribution of plants, has a more direct action on 

 the growth and quality of timber, and requires a 

 short explanation. 



On situation, which involves the idea of the 

 configuration of the earth, rests the difference 

 between the climate of plains and that of mountains. 



CLIMATE OF PLAINS. For a given latitude the 

 climate of plains is generally more uniform than 



