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' ~--,, .. <br />U. S. DEPARTNENT OF AGRICULTURE PAGE S OF 3 <br />NATURAL RESOURCES CONSERVATION SERVICE 02118197 <br />CONSTRUCTION hIATERIALS <br />Endnote -- CONSTRUCTION NATERIALS--Continued <br />Topsoil is used to cover an area so that vegetation can be established and maintained. The upper 60 inches of a soil <br />is evaluated for use as topsoil. Also evaluated is the reclamation potential of the borrov area. Plant growth is <br />affected by toxic material and by such properties as sail reaction, available voter capacity, and fe~tilitY. The ease <br />of ezcavating, loading, and spreading is affected by rock fragments, slope, a water table, sail tezture, and thickness <br />of suitable material. Reclamation of the borrov area is affected ty slope, a water table, rock fragments, bedrock, <br />and tonic material. <br />Soils rata 'Good' have friable loamy material to a depth of~at least 60 inches. they are tree of stones and cobbles, <br />have little or no gravel, and have slopes of less than 8 percent, they are low in content of soluble salts, are <br />naturally fertile er respond well to fertilizer, and ore not so wet that excavation is difficult. <br />Soils rated 'Fair' are sandy soils, loamy soils that have a relatively high content of clay, soils that have only 20 <br />to k0 inches of suitable material, soils that have an appreciable amount of travel, stones, or soluble salts, or <br />soils that have slopes of 8 to 15 percent. The soils are net so wet that ezcavation is difficult. <br />Soils rate 'Poor' are very sandy or clayey, have less than 20 inches of suitable material, have a larue amaint of <br />gravel, stones, or soluble salts, have slopes of mere than 15 percent, er have a seasonal water table at or near the <br />surface. The surface layer of mast sails is Senarally preferred for topsoil 6eca~.ise of it organic matter content. <br />Organic matter greatly increases the absorption and retention of moisture and nutrients for plait Srou;h. <br />