(>4 A I'RIMFK OF FORESTRY. 



air of the forest has less capacity for taking up water 

 vapor than that of the open country. It is also qui- 

 eter, which means that the winds are less active in 

 replacing saturated air with air which can still take up 

 more water. The forest acts powerfully in checking 

 the force of the winds because the elastic swaying of 

 the twi^s and branches is a very effective hindrance to 



FK.. II. A \vin<ll>iv;ik. C;ilit'>nii:i. 



the niovenientof the air. Strong winds, although they 

 are often dangerous in themselves, do most harm by 

 (Irving u]) the moisture in the soil and in the plants 

 which L;TOW from it. Thousands of miles of wind- 

 breaks have been planted by fanners in the western 

 parN of tins country to protect their crops and homes 

 against the wind. 'These windbreak- serve a most use- 

 ful purpose, but they are naturally far less Hlective in 



