ELEMENTS OF GENERAL SCIENCE 



seen (sect. 238). If the forests are removed in mountainous 

 country, the usual result is that the slopes are soon stripped 

 of soil and neither forests or anything else will grow. It is not 

 probable that rainfall is increased by the presence of trees, but 

 the water that does fall is better conserved in the forest than 

 in the open country, and the streams which flow from the 



FIG. 113. Careful lumbering 



The young trees have been protected while the older trees were cut, and the 



brush is piled for burning. After a few years another crop may be harvested. 



Photograph by United States Forest Service 



forested mountains are much more constant and uniform than 

 those that flow from a region whose slopes are bare and rocky. 

 For this reason forests are particularly important when they 

 are located upon the sources of streams which supply water 

 for irrigation in the lower valleys. 



The grasslands in their natural condition are useful mainly 

 for grazing (fig. 115). In the past a large part of the meat 



