Soil series as established by the

National Cooperative Soil Survey The National Cooperative Soil Survey Program (NCSS) in the United States is a nationwide partnership of federal, regional, state, and local agencies and institutions. This partnership works together to cooperatively investigate, inventory, docume ...

of the United States Department of Agriculture (USDA)

Natural Resources Conservation Service Natural Resources Conservation Service (NRCS), formerly known as the Soil Conservation Service (SCS), is an agency of the United States Department of Agriculture (USDA) that provides technical assistance to farmers and other private landowners an ...

are a level of classification in the

USDA Soil Taxonomy USDA soil taxonomy (ST) developed by the United States Department of Agriculture and the National Cooperative Soil Survey provides an elaborate classification of soil types according to several parameters (most commonly their properties) and in sev ...

classification system hierarchy. The actual object of classification is the so-called soil individual, or

pedon A soil horizon is a layer parallel to the soil surface whose physical, chemical and biological characteristics differ from the layers above and beneath. Horizons are defined in many cases by obvious physical features, mainly colour and texture. ...

. Soil series consist of pedons that are grouped together because of their similar

pedogenesis Soil formation, also known as pedogenesis, is the process of soil genesis as regulated by the effects of place, environment, and history. Biogeochemical processes act to both create and destroy order (anisotropy) within soils. These alterations l ...

soil chemistry Soil chemistry is the study of the chemical characteristics of soil. Soil chemistry is affected by mineral composition, organic matter and environmental factors. In the early 1850s a consulting chemist to the Royal Agricultural Society in England, ...

, and physical properties. More specifically, each series consists of pedons having

soil horizons A soil horizon is a layer parallel to the soil surface whose physical, chemical and biological characteristics differ from the layers above and beneath. Horizons are defined in many cases by obvious physical features, mainly colour and texture. ...

that are similar in

soil color Soil color does not affect the behavior and use of soil; however, it can indicate the composition of the soil and give clues to the conditions that the soil is subjected to.Brady, Nyle C. & Ray R. Weil ''Elements of the Nature and Properties of ...

soil texture Soil texture is a classification instrument used both in the field and laboratory to determine soil classes based on their physical texture. Soil texture can be determined using qualitative methods such as texture by feel, and quantitative methods ...

soil structure Soil structure describes the arrangement or the way of soil in the solid parts of the soil and of the pore space located between them. It is determined by how individual soil granules clump, bind together, and aggregate, resulting in the arrangem ...

soil pH Soil pH is a measure of the acidity or basicity (alkalinity) of a soil. Soil pH is a key characteristic that can be used to make informative analysis both qualitative and quantitatively regarding soil characteristics. pH is defined as the neg ...

, consistence, mineral and chemical composition, and arrangement in the

soil profile A soil horizon is a layer parallel to the soil surface whose physical, chemical and biological characteristics differ from the layers above and beneath. Horizons are defined in many cases by obvious physical features, mainly colour and texture. ...

. These result in soils which perform similarly for

land use Land use involves the management and modification of natural environment or wilderness into built environment such as settlements and semi-natural habitats such as arable fields, pastures, and managed woods. Land use by humans has a long h ...

purposes. The soil series concept was originally introduced in 1903. Soil series were originally intended to consist of groups of soils which were thought to be the same in origin but different in texture. Soils were thought to be alike in origin if they were derived from the same kind of rocks or if they were derived in

sediments Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand a ...

derived from the same kind of rocks and deposited at the same time. A soil series name generally is derived from a town or landmark in or near the area where the soil series was first recognized. For example, the Haugan Series was first identified near Haugan, Montana. The distribution of a given series is not necessarily restricted to the boundaries of only one county or state—for example, the Hagerstown Series was first described near

Hagerstown, Maryland Hagerstown is a city in Washington County, Maryland, United States and the county seat of Washington County. The population of Hagerstown city proper at the 2020 census was 43,527, and the population of the Hagerstown metropolitan area (exten ...

, but has also been found as far away as

Tennessee Tennessee ( , ), officially the State of Tennessee, is a landlocked state in the Southeastern region of the United States. Tennessee is the 36th-largest by area and the 15th-most populous of the 50 states. It is bordered by Kentucky to th ...

and

Kentucky Kentucky ( , ), officially the Commonwealth of Kentucky, is a state in the Southeastern region of the United States and one of the states of the Upper South. It borders Illinois, Indiana, and Ohio to the north; West Virginia and Virginia to ...

Relationship to soil mapping

Depending on the context, a soil series may be defined as either a ''taxonomic unit'' or a ''mapping unit''. A taxonomic unit is a category belonging to a specific level of a classification system. It is a conceptual entity that describes the "central nucleus" or essential characteristics of a class. On the other hand, a mapping unit delineates areas of soil in the landscape (i.e. adjacent pedons or polypedons) that possess similar characteristics. The characteristics of a soil series (taxonomic unit) may or may not overlap either fully or partially with the characteristics of pedons within a given mapping unit. Mapping units consist of one or more components. Each component represents polypedons that belong to a particular soil series. The name of a map unit is usually named after the dominant component within the mapping unit. For example, the dominant component of the mapping unit ''LhE—Lily sandy loam, 15 to 35 percent slopes, very stony'' in the

Greenbrier County, West Virginia Greenbrier County () is a county in the U.S. state of West Virginia. As of the 2020 census, the population was 32,977. Its county seat is Lewisburg. The county was formed in 1778 from Botetourt and Montgomery counties in Virginia. History ...

soil survey is the Lily series, which comprises 80% of the mapping unit. The remaining 20% of the mapping unit consists of the Dekalb series, Berks series, and "soils that have stones covering less of the surface" than the Lily series.

References

{{soil science topics Pedology *