420 CONSERVATION 



knows : That streams which flow from issippi, and they have continued their 

 a forested " area rise slowly, carry little growth, though changing in species and 

 sediment, and fall slowly in times of in distribution, while the earth's sur- 

 fiood, and throughout the year are rela- face has been raised to the heights from 

 tively far more uniform in their flow ; which the mountains are being carved, 

 whereas streams which flow from de- During the whole process the forests 

 forested regions rise quickly, carry have conserved and protected the 

 heavy bodies of sediment, and sink ear- mountain slopes from washing, 

 ly in the season of drought to minimum Let us pause to consider the slow 

 low-water stages. changes of the ages that preceded the 

 On the basis of superficial obser\a- advent of man, the destroyer, or pos- 

 tion it is sometimes said that deforesta- sibly the protector, 

 tion as it is now proceeding in the Ap- On a vast plain covering the area of 

 palachian Mountains does not serious- the eastern United States and Canada 

 ly affect the streams, because the forest there grew a luxuriant forest. The 

 which the lumberman cuts is soon re- plain was almost continuous, 

 placed by an aftergrowth. It is true Within the earth titanic forces gath- 

 that the full effect of deforestation fol- e red gradually till their power sufficed 

 lows immediately upon lumbering only to raise the surface slowly and to ele- 

 in extreme cases, but wherever the for- V ate the plain. Rising in a zone that 

 est and the superficial forest soil are reaches from Canada to Alabama the 

 removed a beginning has been made in elevated plain became a plateau from 

 the process of erosion which will ulti- which many rivers flowed to the At- 

 mately remove all the soil. The after- lantic and Pacific. As the slopes steep- 

 growth that follows the severe cutting ened, the waters, falling swiftly, cut 

 and burning under modern lumber con- their channels deeply and made can- 

 ditions is a weakened growth. It never yons, which widened to valleys. Gen- 

 covers the surface as the virgin forest i a l climates favored vegetation, which 

 did ; it is always traversed by freshly during the long, slow process of moun- 

 cut gullies, and the level of channel tain growth and valley carving never 

 grades is sunk below the surface from was removed extensively. Woods pre- 

 a few inches to ten feet or more. The vailed and held the soil, always ad just- 

 advantage thus given to the eroding m g their growth to the very gradual 

 power of thousands of rills is not over- changes of the valley slopes. If per- 

 come by any natural process. Man chance a steep was bared by a sudden 

 alone can so direct and localize a de- landslide it was in time washed clean 

 fense as to make it effective, and he to the hard rock and became a cliff, or 

 does it only at great cost. It is true caved and extended till vegetation 

 that under favorable conditions the soil could take a foothold again. Thus the 

 will maintain itself till the trees of the mountains of to-day were slowly carved 

 aftergrowth become merchantable tim- from the upraised mass, and ever 

 ber, and that the processes of putting, through the ages the forest trees grew 

 burning and partial erosion might un- an( j flourished and died, generation af- 

 cler the most favorable circumstances ter generation, in the soil their roots 

 be continued till several crops had been he j d ast anc | enr i c h e d and deepened, 

 cut from the surface and a half a cen- j t wag tlie - r c ] es tj n y to outlive the 

 tury or more had passed, but the result mountamSj wnO se inert mass must 

 would be deferred merely. That result . w eventuallv to the unceasing at- 

 is to be seen in the bare mountains that - ' d bg wom down 

 stretch from Span, to Asia Minor and * over 



^0^ the wS the forest should stretch its 



Appalachian Mountains; they were living covenng But man has come 



growing throughout the eastern United he holds the forests destiny m his 



States when a great plain stretched un- hands, and his own is intimately 



broken from the Atlantic to the Mis- linked with theirs. 



