235 



streams full. They should be planted everywhere, to briug to this bar- 

 ren region their beneficial influences. 



With trees, as in all things, it is the first step that costs. Each grow- 

 ing tree tends to make its surroundings more adapted to its needs, and 

 as trees are multiplied the climate must necessarily change. The cur- 

 rents of air will be checked and modified, preventing the high winds, 

 sudden changes, and great extremes of temperature. The rain -fall will 

 be retained longer in the ground, providing more moisture for the tree 

 to carry through its leaves to the atmosphere and increasing the hu- 

 midity. The air being moister, there will be more fogs and mists, and 

 consequently more modified and less sunshine and less radiation. Evap- 

 oration will be also retarded by the mechanical obstruction of the 

 branches. All these changes will increase the favorable conditions for 

 the growth of trees, and while we have begun with the native Cotton- 

 wood, we will end with the less vigorous but far more useful sorts. 



Note. — The plauting of trees iu the Eocky Mountain region Las been confined 

 mainly to ornamental and fruit trees, grown in towns and on farms and ranches. 

 Some forest-tree planting has been done under the "timber-culture act," but the re- 

 sults so far are very meager. — B. E. F. 



