SYLVICULTURE. 



denser cover overhead may intercept too much of the needed rain- 

 fall. 



If the climate is too cold, the moisture of the air indeed 

 increases; but the production of seeds and the persistence under 

 cover decrease. 



Y. In mixed forests artificial regeneration is more difficult than 

 natural regeneration. A clean felling results in a capricious com- 

 plication of natural laws and phenomena whose contrary actions 

 are not easily understood. Natural regeneration, a mixture of 

 species suitable to the locality, a crop resembling as closely as pos- 

 sible the primitive state, such are the conditions which the forester 

 should seek to realize for the avoidance of dangers as well as for 

 the greater possible yield of the most valuable produce. No 

 method of treatment harmonizes better with nature's laws than 

 the so-called selection system, when each tree is placed in a con- 

 dition most favorable to its development, and when no single tree 

 is removed for a purpose other than that of regeneration or im- 

 provement of the crop. 



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