Iredell Co NC soil survey cover and soil
John Kelley, Soil Scientist, USDA-NRCS photographing Iredell County landscape. Iredell County is located in the west-central part of North Carolina. It is bordered by Wilkes and Yadkin Counties to the north, Davie and Rowan Counties to the east, Cabarrus and Mecklenburg Counties to the south, and Lincoln, Catawba, and Alexander Counties to the west.
Iredell County Soil Survey report:
archive.org/details/usda-soil-survey-of-iredell-county-no...
The lowest elevations in Iredell County, around 600 feet, occur along Coddle Creek in the southeastern part of the county near the Rowan-Cabarrus County line and along the South Yadkin River near the Davie-Rowan County line. The highest elevations occur in the Brushy Mountains in the northwest part of the county and include Fox Mountain, which has an elevation of about 1,760 feet. Iredell County has a total area of 380,045 acres, or about 594 square miles. Land covers 366,945 acres, and water covers the other 13,100 acres. Lake Norman, which is North Carolina’s largest manmade lake by surface area, extends into the southwest corner of the county. Statesville, the county seat, is in the central part of the county, about 45 miles north of Charlotte, and has a population of about 24,875. Mooresville, the second largest city, is in the southern part of the county and has an estimated population of 20,500. According to 2008 census figures, the county has an estimated population of 155,359. This soil survey updates the survey of Iredell County published in 1964 (USDASCS, 1964). It provides additional information and has larger scaled maps, which show the soils in greater detail.
The update soil survey of Iredell County, North Carolina was conducted to ensure that soils information provided for survey areas within Major Land Resource Area 136 have modern interpretations and up-to-date soil descriptions. This information meets the standards established and defined for the survey area in the memorandum of understanding that was developed among cooperating agencies. Soil surveys that are consistent and uniform within a broad area enable the coordination of management recommendations and uniform program application of soils information.
The survey was made to provide information about the soils and miscellaneous areas in the survey area. The information includes a description of the soils and miscellaneous areas and their location and a discussion of their suitability, limitations, and management for specified uses. Soil scientists observed the steepness, length, and shape of the slopes; the general pattern of drainage; the kinds of crops and native plants; and the kinds of bedrock. They dug many holes to study the soil profile, which is the sequence of natural layers, or horizons, in a soil. The profile extends from the surface down into the unconsolidated material in which the soil formed. The unconsolidated material is devoid of roots and other living organisms and has not been changed by other biological activity.
The soils and miscellaneous areas in the survey area are in an orderly pattern that is related to the geology, landforms, relief, climate, and natural vegetation of the area. Each kind of soil and miscellaneous area is associated with a particular kind of landform or with a segment of the landform. By observing the soils and miscellaneous areas in the survey area and relating their position to specific segments of the landform, a soil scientist develops a concept, or model, of how they were formed. Thus, during mapping, this model enables the soil scientist to predict with a considerable degree of accuracy the kind of soil or miscellaneous area at a specific location on the landscape.
Commonly, individual soils on the landscape merge into one another as their characteristics gradually change. To construct an accurate soil map, however, soil scientists must determine the boundaries between the soils. They can observe only a limited number of soil profiles. Nevertheless, these observations, supplemented by an understanding of the soil-vegetation-landscape relationship, are sufficient to verify predictions of the kinds of soil in an area and to determine the boundaries.
Map unit documentation in the updated survey of Iredell County consists primarily of soil transects conducted by soil scientists. Soil transects are a systematic procedure for sampling a specific soil type. Soil borings are taken at fixed, random, subjectively determined intervals. Soil scientists record the characteristics of the soil profiles that they study. They note soil color, texture, size and shape of soil aggregates, kind and amount of rock fragments, distribution of plant roots, reaction, and other features that enable them to identify soils. This information can then be used to run statistical analyses for specific soil properties. The results of these analyses, along with other observations, enable the soil scientists to assign the soils to taxonomic classes (units).
Taxonomic classes are concepts. Each taxonomic class has a set of soil characteristics with precisely defined limits. The classes are used as a basis for comparison to classify soils systematically. Soil taxonomy, the system of taxonomic classification used in the United States, is based mainly on the kind and character of soil properties and the arrangement of horizons within the profile. After the soil scientists classified and named the soils in the survey area, they compared the individual soils with similar soils in the same taxonomic class in other areas so that they could confirm data and assemble additional data based on experience and research.
While a soil survey is in progress, samples of some of the soils in the area generally are collected for laboratory analyses and for engineering tests. Soil scientists interpret the data from these analyses and tests as well as the field-observed characteristics and the soil properties to determine the expected behavior of the soils under different uses. Interpretations for all of the soils are field tested through observation of the soils in different uses and under different levels of management. Some interpretations are modified to fit local conditions, and some new interpretations are developed to meet local needs. Data are assembled from other sources, such as research information, production records, and field experience of specialists. For example, data on crop yields under defined levels of management are assembled from farm records and from field or plot experiments on the same kinds of soil.
Predictions about soil behavior are based not only on soil properties but also on such variables as climate and biological activity. Soil conditions are predictable over long periods of time, but they are not predictable from year to year. For example, soil scientists can predict with a fairly high degree of accuracy that a given soil will have a high water table within certain depths in most years, but they cannot predict that a high water table will always be at a specific level in the soil on a specific date.
Aerial photographs used in this update survey were taken in 1998. Soil scientists also studied U.S. Geological Survey topographic maps and orthophotographs to relate land and image features. Adjustments of soil boundary lines on the update soil maps were made to coincide with the LiDAR (Light Detection and Ranging) data obtained from the North Carolina Floodplain Mapping Program, including contour lines and tonal patterns on aerial photographs. Aerial photographs also show trees, buildings, fields, roads, and rivers, all of which help in locating boundaries accurately. The descriptions, names, and delineations of the soils in this survey area do not fully agree with those of the soils in adjacent survey areas. Differences are the result of a better knowledge of soils, modifications in series concepts, or variations in the intensity of mapping or in the extent of the soils in the survey areas.
Iredell Co NC soil survey cover and soil
John Kelley, Soil Scientist, USDA-NRCS photographing Iredell County landscape. Iredell County is located in the west-central part of North Carolina. It is bordered by Wilkes and Yadkin Counties to the north, Davie and Rowan Counties to the east, Cabarrus and Mecklenburg Counties to the south, and Lincoln, Catawba, and Alexander Counties to the west.
Iredell County Soil Survey report:
archive.org/details/usda-soil-survey-of-iredell-county-no...
The lowest elevations in Iredell County, around 600 feet, occur along Coddle Creek in the southeastern part of the county near the Rowan-Cabarrus County line and along the South Yadkin River near the Davie-Rowan County line. The highest elevations occur in the Brushy Mountains in the northwest part of the county and include Fox Mountain, which has an elevation of about 1,760 feet. Iredell County has a total area of 380,045 acres, or about 594 square miles. Land covers 366,945 acres, and water covers the other 13,100 acres. Lake Norman, which is North Carolina’s largest manmade lake by surface area, extends into the southwest corner of the county. Statesville, the county seat, is in the central part of the county, about 45 miles north of Charlotte, and has a population of about 24,875. Mooresville, the second largest city, is in the southern part of the county and has an estimated population of 20,500. According to 2008 census figures, the county has an estimated population of 155,359. This soil survey updates the survey of Iredell County published in 1964 (USDASCS, 1964). It provides additional information and has larger scaled maps, which show the soils in greater detail.
The update soil survey of Iredell County, North Carolina was conducted to ensure that soils information provided for survey areas within Major Land Resource Area 136 have modern interpretations and up-to-date soil descriptions. This information meets the standards established and defined for the survey area in the memorandum of understanding that was developed among cooperating agencies. Soil surveys that are consistent and uniform within a broad area enable the coordination of management recommendations and uniform program application of soils information.
The survey was made to provide information about the soils and miscellaneous areas in the survey area. The information includes a description of the soils and miscellaneous areas and their location and a discussion of their suitability, limitations, and management for specified uses. Soil scientists observed the steepness, length, and shape of the slopes; the general pattern of drainage; the kinds of crops and native plants; and the kinds of bedrock. They dug many holes to study the soil profile, which is the sequence of natural layers, or horizons, in a soil. The profile extends from the surface down into the unconsolidated material in which the soil formed. The unconsolidated material is devoid of roots and other living organisms and has not been changed by other biological activity.
The soils and miscellaneous areas in the survey area are in an orderly pattern that is related to the geology, landforms, relief, climate, and natural vegetation of the area. Each kind of soil and miscellaneous area is associated with a particular kind of landform or with a segment of the landform. By observing the soils and miscellaneous areas in the survey area and relating their position to specific segments of the landform, a soil scientist develops a concept, or model, of how they were formed. Thus, during mapping, this model enables the soil scientist to predict with a considerable degree of accuracy the kind of soil or miscellaneous area at a specific location on the landscape.
Commonly, individual soils on the landscape merge into one another as their characteristics gradually change. To construct an accurate soil map, however, soil scientists must determine the boundaries between the soils. They can observe only a limited number of soil profiles. Nevertheless, these observations, supplemented by an understanding of the soil-vegetation-landscape relationship, are sufficient to verify predictions of the kinds of soil in an area and to determine the boundaries.
Map unit documentation in the updated survey of Iredell County consists primarily of soil transects conducted by soil scientists. Soil transects are a systematic procedure for sampling a specific soil type. Soil borings are taken at fixed, random, subjectively determined intervals. Soil scientists record the characteristics of the soil profiles that they study. They note soil color, texture, size and shape of soil aggregates, kind and amount of rock fragments, distribution of plant roots, reaction, and other features that enable them to identify soils. This information can then be used to run statistical analyses for specific soil properties. The results of these analyses, along with other observations, enable the soil scientists to assign the soils to taxonomic classes (units).
Taxonomic classes are concepts. Each taxonomic class has a set of soil characteristics with precisely defined limits. The classes are used as a basis for comparison to classify soils systematically. Soil taxonomy, the system of taxonomic classification used in the United States, is based mainly on the kind and character of soil properties and the arrangement of horizons within the profile. After the soil scientists classified and named the soils in the survey area, they compared the individual soils with similar soils in the same taxonomic class in other areas so that they could confirm data and assemble additional data based on experience and research.
While a soil survey is in progress, samples of some of the soils in the area generally are collected for laboratory analyses and for engineering tests. Soil scientists interpret the data from these analyses and tests as well as the field-observed characteristics and the soil properties to determine the expected behavior of the soils under different uses. Interpretations for all of the soils are field tested through observation of the soils in different uses and under different levels of management. Some interpretations are modified to fit local conditions, and some new interpretations are developed to meet local needs. Data are assembled from other sources, such as research information, production records, and field experience of specialists. For example, data on crop yields under defined levels of management are assembled from farm records and from field or plot experiments on the same kinds of soil.
Predictions about soil behavior are based not only on soil properties but also on such variables as climate and biological activity. Soil conditions are predictable over long periods of time, but they are not predictable from year to year. For example, soil scientists can predict with a fairly high degree of accuracy that a given soil will have a high water table within certain depths in most years, but they cannot predict that a high water table will always be at a specific level in the soil on a specific date.
Aerial photographs used in this update survey were taken in 1998. Soil scientists also studied U.S. Geological Survey topographic maps and orthophotographs to relate land and image features. Adjustments of soil boundary lines on the update soil maps were made to coincide with the LiDAR (Light Detection and Ranging) data obtained from the North Carolina Floodplain Mapping Program, including contour lines and tonal patterns on aerial photographs. Aerial photographs also show trees, buildings, fields, roads, and rivers, all of which help in locating boundaries accurately. The descriptions, names, and delineations of the soils in this survey area do not fully agree with those of the soils in adjacent survey areas. Differences are the result of a better knowledge of soils, modifications in series concepts, or variations in the intensity of mapping or in the extent of the soils in the survey areas.