290 SOIL EROSION 



strength of the sod or the hold of the bushes that may be planted 

 on the balks, while the belts of plowland become level, or the slope 

 of the benches is slightly reversed. When the benches become 

 level, it is necessary to maintain only small shoulders about one- 

 half a foot high at their outer edges. 



Bench terraces should have no fall along the direction of their 

 length. The level of the benches may be maintained or their 

 slope regulated by plowing by turning the furrow slices inward 

 or outward as conditions may require. 



In ridge terracing, the ridges are often cropped, or the field 

 is planted and cultivated as if no ridges were present. In either 

 bench or ridge terracing, the rain water that falls on a belt of 

 plowland is collected and held above the lower terrace until it 

 evaporates, sinks into the soil or finds its way slowly to an outlet 

 at the ends of the terraces. 2 



Terracing is most commonly practiced in the Southern states. 



STOPPING WASHING AND RECLAIMING ERODED LANDS 



In stopping washes and in reclaiming eroded lands, it is neces- 

 sary to make use of all the methods employed in prevention. 

 Aside from these there are many other methods employed in stop- 

 ping the advance of ditches and in filling gullies. 



Reforesting. Most frequently lands which cannot be used for 

 farming because of excessive erosion must be reforested in order 

 to be reclaimed. Trees should be planted thickly in the mouths 

 of, and as far up, the gullies as possible. 



Otiier Measures. Straw or similar material is usually of much 

 help in stopping or filling small gullies. Sometimes washes may be 

 stopped by dragging in some dirt and sowing sorghum thickly. 

 Often ditches may be filled with straw and debris, and dirt plowed 

 in on top and seeded with grass, sorghum or grass. Brush, logs, 

 stumps and stones are excellent materials to throw into gullies 

 (Fig. 192). Such material should be well anchored to prevent its 

 being carried away. Many ditches have been completely filled in 

 this manner. Sometimes dams of wire, mesh, boards, brush and 

 reinforced concrete are quite satisfactory for certain locations in 

 preventing further erosion, or in reclamation. Usually such dams 

 will gradually allow the gully above to fill with sediment (Figs. 

 192 and 193). The planting of willows or bushes along the edges 

 of a gully is often effective in stopping further erosion. 



2 United States Farmers' Bulletin 997. 



