Forests an Important Factor in the Economy of Nature 



forests, as producers of fuel and lum- 

 ber, with all the uses to which these are 

 put, to say nothing of by-products, are 

 intimately connected with the welfare 

 of men. Many of them live by working 

 at trades either directly or indirectly 

 dependent on them. 



\Yhat position do the forests hold in 

 the economy of nature, that is, in the re- 

 lations and interworkings of what 

 we may call its four primal factors- 

 the animal, vegetable, and mineral 

 kingdoms? These are closely con- 

 nected with one another. For ex- 

 ample, animal and vegetable life 

 are especially interdependent, not 

 only as regards the furnishing one 

 to the other of the essentials of 

 existence, but also in their relation to 

 the atmosphere a matter of great con- 

 cern to man. Tt has often been shown 



that the same carbonic acid gas which 

 is destructive for animal life, is an es- 

 sential for vegetable life. Plants need 

 this gas to develop their organs, and 

 in turn emit oxygen, which is equally 

 vital to animals. All plants, but par- 

 ticularly areas of trees with their 

 wealth of foliage, are instrumental in 

 effecting this exchange of gases ; hence, 

 any discussion of the chemistry of the 

 atmosphere has to take into account 

 the great and real influence of the 

 woodlands. A beech wood, which fur- 

 nishes on one hectare f) l / 2 feet of w-ood 

 in a year, will in this period throw off 

 51,567 cubic feet of oxygen, enough 

 for the requirements, in that regard, of 

 eight adults the same length of time. 

 But while thus fitting the atmosphere 

 for animal life, trees with their green 

 leaves and branches bind the carbon of 



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