Figure 10. Mountain 

 stream bordered by 

 steep, wooded slopes 

 which check run-off and 

 erosion and lessen 

 freshets. 



I. S. FOREST SERVICE 



Figure 11. The litter, 

 undisturbed soil, and 

 root system under this 

 lone tree resists the en- 

 circling erosion. 



U. S. SOIL CONSERVATION SERVICE 



Figure 12. Close-up of 

 forest litter an agent 

 that retards surface flow 

 and filters absorbed 

 water. 



U. S. FOREST SERVICE 



