Forestry and Government 167 



greatly reduced on account of the destruction of 

 forests. It has not been established, however, that 

 these countries had a very much larger forest area 

 in ancient times, or that with rational methods of 

 agriculture they would not be as productive to-day 

 as they ever were. Just so it would be pretty 

 hard to prove that any considerable portion of the 

 North American continent is in danger of being 

 turned into a desert on account of the destruction 

 of forests, even if it proceeded with much greater 

 rapidity. The whole question of the influence of 

 forests on climate is still under investigation, and 

 many more and systematic observations are neces- 

 sary before it can be considered settled. 



However, a few facts in this regard may be taken 

 as above dispute. It is not improbable that the 

 extent to which the general climate of a country is 

 affected by forests is overrated, but they certainly 

 affect the conditions in their own immediate vicin- 

 ity. The absence from forest areas of the hot, 

 scorching winds so inimical to agriculture on our 

 treeless plains is one of the instances of such influ- 

 ence. Large areas of forest also seem to have a 

 tendency, similar to large bodies of water, to lower 

 the average temperature of summer and raise that 

 of winter, but this is more doubtful. Whether 

 forests tend to increase rainfall, as is often asserted, 

 is, to say the least, not proven. The most con- 

 spicuous and best ascertained effect of forests upon 

 natural conditions is the manner in which they 

 regulate the flow of streams and surface water. 



