Water in the Soil 75 



slope is very gradual. Uncultivated lands are protected 

 from devastating washings by their coverings of grass, 

 weeds, and other forms of vegetation. The latter retard 

 the flow of the surface water, and therefore allow more 

 of it to soak into the soil. 



In preventing injury by too rapid surface drainage, 

 or in recovering land that has been injured by washings, 

 several working principles have been proposed, which 

 may be applied with success, either singly or in com- 

 binations, to suit the local circumstances: 



(a) By Terracing. This consists in breaking the slope 

 up into a number of terraces, or level belts, with sharply 

 sloping sides, such as may be observed on a very large 

 scale along the shores of lakes or water courses. The ter- 

 races are made nearly level, so that the rain is kept on 

 the land longer, and therefore facilitates absorption and 

 allows the excess to flow off slowly. Terraces are pref- 

 erable to the old-time hillside ditches. The latter quite 

 often magnify the trouble they were intended to pre- 

 vent. Objections are made to terracing because of the 

 great cost of construction and the increased cost of cul- 

 tivation. Also, because a part of the land is left uncul- 

 tivated, and therefore likely to grow up in weeds. The 

 practice of running the rows on a level around a hillside 

 may be considered a form of terracing. 



(b) By Deep Breaking, or keeping the absorptive 

 power of the soil to a point where moderate rains will 

 be readily absorbed, (f 105.) 



(c) By Growing Cover-crops (U 144) which not only 

 protect the land while they are on the land, but also 

 add vegetable matter which tends to bind the soil to- 

 gether. Soils in southern climates usually contain less 

 vegetable matter, and therefore suffer more from wash- 



