Arkansas-White-Red Basins Inter-Agency Committee Purpose, Organization and Plan for Public Hearings

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0% The long -range program of the Forest Service calls for the completion of topographic maps of standard content, at the scale of one inch equals one mile for general administrative use. 9. Soil Surveys (Ref: LC in U.S. 1941, p. 58) "The work of the Soil Survey is properly to be regarded as land classi- fication, inasmuch as it classifies bodies -of land in terms of their inherent soil characteristics. It is an integral part of a comprehensive study of soils leading to an understanding of their best use. Concurrent with the classi- fication and mapping of the soil units, other research is required to ascertain the responsiveness of specific soils to management and the capabilities of each for use. This.research is not a function of the_Soil Survey alone, but Is conducted by cooperating research groups in the Department of Agriculture and in the.State agricultural experiment stations throughout the country. The.work. of these agencies leads ultimately to a classification of the soil types according to their potentialities for use. This classifications which can be regarded as a type of land classification, is being..developed in conjunction with the Soil Survey .. a ..." "The identification and mapping of soil types, with which the Soil Survey is primarily concerned, provides a means of applying to specific geographic areas or individual farms the results of research dealing with the use and capabilities of soils and their response to management. It is plain that without having mapped soil types, that is, bodies of`soil.having the same characteristics, wherever they occur, there is no way of knowing the geo- graphic extent to which experience gained on a particular soil can be applied" "In order to .locate the soil areas properly, it is necessary to have an accurate base map. The most satisfactory base for making detailed soil maps in the field is a single -lens aerial photograph of good quality. Few other base maps provide as many points of reference for. the location of soil. features." "Formerly field mapping of soils was done upon tcpographie maps of the United States .Geologioal Survey. If the -se or some other base maps were not available, base maps were constructed by plane table traverse. "Aerial photographs used for soil survey. field base are most commonly on scales of 3.16 or 4 inches -to -the- mile. Plane-table-mapping is usually done at a scale of .2.inches -to- the - mile. -However, departures from these scales are made where special circumstances require it." "The results of the soil survey are published in reports. In most cases 'a report covers the work done in one county.. In the West where agriculture is frequently localized: in irrigated 'valleys, reports are commonly issued for 'areas' covering less than a county." "The soil map accompanying the report is a lithographed colored map, in most instances on a scale of one inch equals one.mile ...... o....o— o Larger scales than this are sometimes used where special conditions require." C -6