elements, as no longer useful. While being cultivated and fre- 

 quently stirred the land will rarely be allowed to seriously wash. 

 If the surface has slopes and nearly all our lands have decided 

 slopes in cultivation it is either terraced or circled to prevent 

 washing, and any wash that begins is filled with brush, or other- 

 wise arrested. Not so when it is once thrown out, as so much 

 of our land has been. 



The heavy torrential rains that fall frequently in our climate 

 s<oon furrow the slopes ; if the slopes are steep the furrows 

 quickly become gullies, and within a few years these may become 

 tremendous washes, fifteen to twenty-five feet deep, and large 

 enough to engulf a moderate-sized house. If the soil be sandy, 

 or if underlaid by a sandy stratum a few feet beneath the surface, 

 the destruction is all the more rapid. Beginning as they generally 

 do on the lower slopes, these washes eat back farther and farther 

 into the abandoned lands until the whole surface becomes cut to 

 pieces. 



Who of us have not seen what was once a field of swelling, 

 graceful slopes now presenting an intricate maze of gullies and 

 washes, until the original surface remains only as narrow crests 

 between yawning chasms, or as clustered peaks and buttes which 

 are but the finger marks of an even greater destruction. And all 

 this because man has withdrawn his intelligent use of the soil. 

 It may be asked, What are the conditions favoring this state of 

 things ? How do they operate ? They are briefly stated below". 



i. Slopes especially steep slopes. Since all soils are moving 

 toward the sea, which is their final resting place, it is evi- 

 dent that the steeper the slopes, other things being equal, the more 

 rapid the removal will be. Hence, hilly lands, which have steep 

 slopes, will wash most rapidly. The erosive power of running 

 water varies with the square root of the velocity of flow, and 

 since slope is the chief factor affecting velocity it will be readily 

 understood why it is that washing begins on the steeper slopes 

 of abandoned fields. 



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