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Ref.Page No. M2009-006 00093 <br /> Custom Soil Resource Report <br /> HowSoi[Surveys Are Made <br /> Soil surveys are made to provide information about the soils and miscellaneous areas in a <br /> specific area. They include a description of the soils and miscellaneous areas and their <br /> location on the landscape and tables that show soil properties and limitations affecting <br /> various uses. Soil scientists observed the steepness, length, and shape of the slopes; the <br /> general pattern of drainage; the kinds of crops and native plants; and the kinds of bedrock. <br /> They observed and described many soil profiles. A soil profile is the sequence of natural <br /> layers, or horizons, in a soil. The profile extends from the surface down into the <br /> unconsolidated material in which the soil formed or from the surface down to bedrock. The <br /> unconsolidated material is devoid of roots and other living organisms and has not been <br /> changed by other biological activity. <br /> Currently, soils are mapped according to the boundaries of major land resource areas <br /> (MLRAs). MLRAs are geographically associated land resource units that share common <br /> characteristics related to physiography, geology, climate, water resources, soils, biological <br /> resources, and land uses (USDA, 2006). Soil survey areas typically consist of parts of one <br /> or more MLRA. <br /> The soils and miscellaneous areas in a survey area occur in an orderly pattern that is related <br /> to the geology, landforms, relief, climate, and natural vegetation of the area. Each kind of <br /> soil and miscellaneous area is associated with a particular kind of landform or with a <br /> segment of the landform. By observing the soils and miscellaneous areas in the survey area <br /> and relating their position to specific segments of the landform, a soil scientist develops a <br /> concept, or model, of how they were formed. Thus, during mapping, this model enables the <br /> soil scientist to predict with a considerable degree of accuracy the kind of soil or <br /> miscellaneous area at a specific location on the landscape. <br /> Commonly, individual soils on the landscape merge into one another as their characteristics <br /> gradually change. To construct an accurate soil map, however, soil scientists must <br /> determine the boundaries between the soils. They can observe only a limited number of soil <br /> profiles. Nevertheless, these observations, supplemented by an understanding of the soil- <br /> vegetation-landscape relationship, are sufficient to verify predictions of the kinds of soil in <br /> an area and to determine the boundaries. <br /> Soil scientists recorded the characteristics of the soil profiles that they studied. They noted <br /> soil color, texture, size and shape of soil aggregates, kind and amount of rock fragments, <br /> distribution of plant roots, reaction, and other features that enable them to identify soils. After <br /> describing the soils in the survey area and determining their. properties, the soil sc entists <br /> assigned the soils to taxonomic classes (units). <br /> Taxonomic classes are concepts. Each taxonomic class has a set of soil characteristics with <br /> precisely defined limits. The classes are used as a basis for comparison to classify soils <br /> systematically. Soil taxonomy, the system of taxonomic classification used in the United <br /> States, is based mainly on the kind and character of soil properties and the arrangement of <br /> horizons within the profile. After the soil scientists classified and named the soils in the <br /> survey area, they compared the individual soils with similar soils in the same taxonomic <br /> class in other areas so that they could confirm data and assemble additional data based on <br /> experience and research. <br /> The objective of soil mapping is not to delineate pure map unit components;the objective is <br />