Plymouth County Soil Survey Update
Classification
of the Soils
Link
to Keys to Soil Taxonomy (Complete Description)
Click here for Soil Series Classification Table
Have you ever wondered what a Birchwood, Sandy over loamy, mixed, nonacid, mesic Aquic Udorthents is?
One of the fundamental responsibilities of any branch of science is to use a systematic way to group things into categories on shared characteristics or traits, referred to taxonomy. Biologists use the Linneaus Taxonomic system to classify living organisms. This system groups organisms into Kingdoms, Divisions, Classes, Orders, Families, Genus, and Species. The Genus and species of the organism gives the scientific name for the organism. Soil Scientists use various taxonomic systems to classify soils throughout the world.
The system of soil classification used by the National Cooperative Soil Survey has six categories. Beginning with the broadest, these categories are the order, suborder, great group, subgroup, family, and series. Classification is based on soil properties observed in the field or inferred from those observations or from laboratory measurements. The classification of the soils in Plymouth County, Massachusetts is listed in the classification table linked above. The categories are defined in the following paragraphs.
ORDER. Twelve soil orders are recognized. The differences among orders reflect the dominant soil-forming processes and the degree of soil formation. Each order is identified by a word ending in sol (an example is Entisol). In Plymouth County four soil orders have been identified and classified. Histosols (histos, Greek for tissue) are soils formed in at least 16 inches of organic sediments. Spodisoils (spodos, Greek for wood ashes) are soils with subsoil accumulations of iron, aluminum and humus. Inceptisols (inceptum, Latin for beginning), are soils with minimal pedogenic (soil) development. Entisoils (recent), recenty formed or created soils. For information about the formation or genesis of the soils in Plymouth County click HERE.
SUBORDER. Each order is divided into suborders primarily on the basis of properties that influence soil genesis and are important to plant growth or properties that reflect the most important variables within the orders. The last syllable in the name of a suborder indicates the order. An example is Aquent (Aqu, meaning water, plus ent, from Entisol).
GREAT GROUP. Each suborder is divided into great groups on the basis of close similarities in kind, arrangement, and degree of development of pedogenic horizons; soil moisture and temperature regimes; and base status. Each great group is identified by the name of a suborder and by a prefix that indicates a property of the soil. An example is Haplaquents (Hapl, meaning minimal horizonation, plus aquent, the suborder of the Entisols that has an aquic moisture regime).
SUBGROUP. Each great group has a typic (typical) subgroup. Other subgroups are intergrades or extragrades. The typic is the central concept of the great group; it is not necessarily the most extensive. Intergrades are transitions to other orders, suborders, or great groups. An example of an intergrade in Plymouth County is the Carver Series which is a Spodic Quartzipsamment meaning, it's an Entisol (ent) but has slight spodic development, hence the Spodic subgroup intergrade. It is reasonable to expect the Carver series to become a Spodosol over a period of time but it is currently too young to classify as a Spodosol. Extragrades have some properties that are not representative of the great group but does not indicate transitions to any other known kind of soil. Each subgroup is identified by one or more adjectives preceding the name of the great group. The adjective Typic identifies the subgroup that typifies the great group. An example is Typic Haplaquents.
FAMILY. Families are established within a subgroup on the basis of physical and chemical properties and other characteristics that affect management. Mostly the properties are those of horizons below plow depth where there is much biological activity. Among the properties and characteristics considered are particle-size class, mineral content, temperature regime, depth of the root zone, consistence, moisture equivalent, slope, and permanent cracks. A family name consists of the name of a subgroup preceded by terms that indicate soil properties. An example is fine-loamy, mixed, nonacid, mesic Typic Haplaquents.
SERIES. The series consists of soils that have similar horizons in their profile. The horizons are similar in color, texture, structure, reaction, consistence, mineral and chemical composition, and arrangement in the profile. Soil series are typically named after a geographic location the soil was first described and mapped. In Plymouth County 55 soil series are currently (January 2000) being mapped, 5 new series were classified and named during the course of the soil survey update. Soil series are further broken down into various phases based on various properties such as the texture of the surface layer, stoniness or slope.
SOIL CLASSIFICATION January 2000(Link to Keys to Soil Taxonomy)
Underlined series are hydric soils (Link to Hydric Soil Homepage)
8th edition of Soil Taxonomy
Barnstable, Coarse-loamy over sandy or sandy-skeletal, mixed, active, mesic Typic Dystrochrepts
Berryland, Sandy, siliceous, mesic Typic Alaquods
Birchwood, Sandy over loamy, mixed, nonacid, mesic Aquic Udorthents
Birdsall, Coarse-silty, mixed, nonacid, mesic Typic Humaquepts
Broadbrook, Coarse-loamy, mixed, active, mesic Oxyaquic Dystrudepts
Brockton, Sandy, mixed, mesic Typic Humaquepts
Canton, Coarse-loamy over sandy or sandy-skeletal, mixed, mesic Typic Dystrochrepts
Carver Mesic, uncoated Typic Quartzipsamments
Chatfield, Coarse-loamy, mixed, superactive, mesic Typic Dystrochrepts
Deerfield, Mixed, mesic Aquic Udipsamments
Eldridge, Sandy over loamy, mixed, active, nonacid, mesic Aquic Udorthents
Enosburg, Sandy over loamy, mixed, active, nonacid, mesic Aeric Epiaquents
Freetown, Dysic, mesic Typic Medisaprists
Gloucester, Sandy-skeletal, mixed, mesic Typic Dystrochrepts
Haven, Coarse-loamy over sandy or sandy-skeletal, mixed, mesic Typic Dystrochrepts
Hinckley, Sandy-skeletal, mixed, mesic Typic Udorthents
Hinesburg, Sandy over loamy, mixed, nonacid, mesic Typic Udorthents
Hooksan, Mesic, uncoated, Typic Quartzipsamments
Ipswich, Euic, mesic Typic Sulfihemists
Limerick, Coarse-silty, mixed, active, nonacid, mesic Typic Fluvaquents
Mattapoisett, Sandy, mixed, mesic, ortstein Typic Epiaquods
Matunuck, Sandy, mixed, mesic Typic Sulfaquents
Merrimac, Sandy, mixed, mesic Typic Dystrochrepts
Montauk, Coarse-loamy, mixed, subactive, mesic Oxyaquic Dystrochrepts
Newfields, Coarse-loamy over sandy or sandy-skeletal, mixed, active, mesic Oxyaquic Dystrochrepts
Newport, Coarse-loamy, mixed, mesic Typic Dystrochrepts
Norwell, Sandy, mixed, mesic, shallow Aeric Epiaquents
Pawcatuck, Sandy or sandy-skeletal, mixed, euic, mesic Terric Sulfihemists
Paxton, Coarse-loamy, mixed, active, mesic Oxyaquic Dystrudepts
Pipestone, Sandy, mixed, mesic Typic Endoaquods
Pittstown, Coarse-loamy, mixed, mesic Aquic Dystrochrepts
Plymouth, Mesic, coated Typic Quartzipsamments
Poquonock, Sandy over loamy, mixed, nonacid, mesic Typic Udorthents
Quonset, Sandy-skeletal, mixed, mesic Typic Udorthents
Rainbow, Coarse-loamy, mixed, active, mesic Aquic Dystrudepts
Raynham, Coarse-silty, mixed, active, nonacid, mesic Aeric Epiaquepts
Ridgebury, Coarse-loamy, mixed, active, nonacid, mesic Aeric Epiaquepts
Saco, Coarse-silty, mixed, active, nonacid, mesic Fluvaquentic Humaquepts
Saugatuck, Sandy, mixed, mesic, ortstein Typic Duraquods
Scarboro, Sandy, mixed, mesic Histic Humaquepts
Scio, Coarse-silty, mixed, mesic Aquic Dystrochrepts
Scituate, Coarse-loamy, mixed, mesic Oxyaquic Dystrochrepts
Sippican, Sandy, mixed, mesic Histic Humaquepts
Sudbury, Sandy, mixed, mesic Aquic Dystrochrepts
Swansea, Sandy or sandy-skeletal, mixed, dysic, mesic Terric Medisaprists
Tisbury, Coarse-silty over sandy or sandy-skeletal, mixed, active, mesic Aquic Dystrudepts
Walpole, Sandy, mixed, mesic Aeric Endoaquepts
Wapanucket, Mixed, mesic Typic Udipsamments
Wareham, Mixed, mesic Humaqueptic Psammaquents
Windsor, Mixed, mesic Typic Udipsamments
Winooski, Coarse-silty, mixed, nonacid, mesic Aquic Udifluvents
Whitman, Coarse-loamy, mixed, active, nonacid, mesic Typic Humaquepts
Woodbridge, Coarse-loamy, mixed, active, mesic Aquic Dystrudepts
