Laserfiche WebLink
to Ob <br />J I <br />Exhibit 9a is a map of the United States dated April 1919 (Scale. One <br />inch equals 110 miles) showing "Areas Covered by the Soil Survey: <br />Exhibit 9b is a similar map (letter -size) of the United States, dated <br />January 1950, showing the more generalized picture of the areas covered by <br />the Soil Survey. <br />10. Conservation Surveys of the Soil Conservation Service (Ref: LC in <br />U. S. 1941, p• 65) <br />"Land classification forms an important part of the technical service <br />provided by the Soil Conservation Service to help farmers set up and follow <br />plans for soil and water conservation. The work is known as conservation <br />surveys. Its purpose is to provide a physical basis for drawing up farm <br />conservation plans. A farm conservation plan is made for each farm which <br />cooperates with the Soil Conservation Service in carrying on a soil con - <br />servation demonstration, and for each farm in a soil conservation district <br />which enters into an agreement with the district to carry on soil conserving <br />measures. The farm conservation plan is the basis of cooperation between <br />the farmer and his soil conservation district." <br />"The conservation survey typically involves the snapping of four items, <br />namely soil type, percent of slope, condition of erosion, and present land <br />use. It involves also the classification of the land types mapped according <br />to their capabilities for agricultural use." <br />"The field mapping in detailed conservation surveys is done most <br />commonly on aerial photographs on a scale of four inches to the mile. As <br />a rule these are enlarged to 8 inches to the mile for use by the farm planning <br />technicians in working out and portraying farm conservation plans. Such <br />plans include field layouts, crop strips, terraces, and water disposal systems. <br />In some areas with a very intricate or intensive pattern of agriculture, <br />photographs on a scale of 8 inches to the mile may be used for field mapping. <br />Reconnaissance conservation surveys are made at scales of 2 inches, 1 inch, <br />or even a half inch to the mile." <br />"The nature of the soil, the slope, and the kind and degree of erosion <br />all influence the nature and intensity of practices that are necessary for <br />conservation and good use of the land. After the three factors have been <br />mapped they furnish a basis for classifying the land in order to indicate <br />its use and capability. This classification is a summation that directs <br />attention specifically to two questions: (1) Is the land suitable for <br />agricultural use? (2).What kind of practices (soil erosion control or other) <br />are required, and how intensely must they be applied ?" <br />Exhibit 10a is a map of the United States showing the "Extent of Soil <br />Conservation Surveys" as of January 1950. <br />11. Bureau of Reclamation (Refs LC in U.S. 1941, p. 71) <br />The Bureau of Reclamation has made topographic surveys in connection <br />with project investigations at several points. In the main, these topo- <br />graphic surveys consist of maps of small and rather limited areas such as <br />reservoir sites, dam sites, project lands and strip topography along <br />C -7 <br />