1516 



AMERICAN FORESTRY 



productive. Other examples of the damage resulting 

 from interference with the forest cover before the crea- 

 tion of the National Forests can be selected almost at 

 random from 

 the Mountain 

 Forests of the 

 West. In the 

 Sangre de 

 Cristo Range 

 and the Green- 

 horn Range, in 

 what is now the 

 San Isabel Na- 

 tional Forest, 

 iii s o u t hern 

 Colorado, it is 

 very noticeable 

 that s t r earns 

 whose head- 

 waters have 

 been denuded 

 to a considera- 

 ble extent of 

 their protective 

 cover have 

 badly eroded 

 channels and 

 are subject to 

 great extremes 

 in flow, with 

 f r e q uent de- 

 structive floods, 

 while no harm- 

 ful effects of 

 this sort are 

 noticeable o n 

 streams whose 

 headwaters are 

 well timbered. 

 Wild Cherry 

 Creek, for ex- 

 ample, after 

 being almost 

 complete ly 

 burnt over, 

 was subject to 

 spring floods 

 and to damage 

 from erosion. 

 During July it 

 would dry up 

 at a distance 

 of not over 2 

 miles from the 

 mouth of the 

 canyon. As the 

 watershed has become reforested these conditions have 

 changed gradually until today the stream is not subject 

 to floods and erosion and is more regular in its flow. 



WHAT TOO RAriD RUNOFF CAN DO 



Upper. — Boulders for soil. This view of the Santa Ana River in southern California shows how torrential 



run-off may wash away the soil and leave the land covered with snags, gravel, bowlders, and 



other infertile debris. 

 Lower. — Sand for alfalfa. The sand waste in the foreground is typical of hundreds of acres of formerly 



good alfalfa land along the San Diego River in southern California which were seriously 



damaged by the flood of January, 1916. 



During the summer it now reaches a point 4 miles 

 below the mouth of the canyon and is used early in the 

 fall for irrigation. Apache Creek, which formerly flowed 



the full length 

 of its course all 

 summer, since 

 the destruction 

 of the timber 

 at its head- 

 w a t ers disap- 

 pears only 2 or 

 3 miles from its 

 head ; and its 

 only value for 

 irrigation pur- 

 poses after the 

 middle of June 

 lies in its flood 

 waters, which 

 are very un- 

 certain. Hard- 

 scrabble and 

 Medano Creeks 

 have suffered 

 similar results, 

 and the list 

 might be ex- 

 ex t e n ded al- 

 most indefinite- 



ly. 



On the North 

 Fork of the 

 Gunnison 

 River, in west- 

 ern Colorado, 

 much flood 

 damage has oc- 

 curred as a re- 

 sult of the ex- 

 tensive fires 

 which burned 

 over its upper 

 watersheds in 

 the late seven- 

 ties and early 

 eighties. Pre- 

 vious to that 

 time the creek 

 channels were 

 narrow and 

 rocky, beavers 

 were abundant, 

 and the bottom 

 lands showed 

 little e r osion. 

 In 1884 a 

 heavy snowfall was followed by a flood which is esti- 

 mated to have ruined at least 2,000 acres of good ranch 

 land. Since then destructive floods have occurred every 



