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A representative soil profile of the Nineveh series. (Soil Survey of Bartholomew County, Indiana; by Mike Wigginton and Dena Marshall, Natural Resources Conservation Service)
The Nineveh series consists of very deep, well drained soils that are moderately deep to calcareous, stratified gravelly and sandy outwash. The Nineveh soils formed in loamy deposits. They are on stream terraces. Slope ranges from 0 to 6 percent. Mean annual precipitation is about 1041 mm (41 inches), and mean annual air temperature is about 11 degrees C (52 degrees F).
TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, active, mesic Typic Argiudolls
Thickness of the solum: 61 to 102 cm (24 to 40 inches)
USE AND VEGETATION: Nineveh soils are mostly cultivated. The principal crops grown are corn, soybeans, wheat, and hay. Some areas are used for growing green beans, potatoes, tomatoes, strawberries, and other vegetables and fruits. Irrigation is used on this soil in some areas. Native vegetation is prairie grass with widely spaced trees, chiefly oak, hawthorn, walnut, and wild cherry.
DISTRIBUTION AND EXTENT: Central and south-central Indiana and western Ohio; MLRA 111A. The series is of moderate extent, about 20,000 acres.
For additional information about the survey area, visit:
www.nrcs.usda.gov/Internet/FSE_MANUSCRIPTS/indiana/IN005/...
For a detailed soil description, visit:
soilseries.sc.egov.usda.gov/OSD_Docs/N/NINEVEH.html
For acreage and geographic distribution, visit:
A soil that meets the requirements of indicator F6 must have a dark surface layer with value of 3 or less and chroma of 2 or less and redox concentrations in the dark layer.
These soils have a layer that is at least 10 cm (4 inches) thick, starting at a depth ≤20 cm (8 inches) from the mineral soil surface, and has:
a. Matrix value of 3 or less and chroma of 1 or less and 2 percent or more distinct or prominent redox concentrations occurring as soft masses or pore linings, or
b. Matrix value of 3 or less and chroma of 2 or less and 5 percent or more distinct or prominent redox concentrations occurring as soft masses or pore linings.
User Notes: This is a very common indicator used to delineate wetland soils that have a dark surface layer. Redox concentrations in mineral soils with a high content of organic matter and a dark surface layer are commonly small and difficult to see (figs. 30, 31, and 32). The organic matter masks some or all of the concentrations that may be present. Careful examination is required to see what are commonly brownish redox concentrations in the darkened materials. If the soil is saturated at the time of sampling, it may be necessary to let it dry at least to a moist condition for redox features to become visible. Soils that are wet because of ponding or have a shallow, perched layer of saturation may have any color below the dark surface. It is recommended that delineators evaluate the hydrologic source and examine and describe the layer below the dark colored surface layer when applying this indicator.
Field Indicators of Hydric Soils in the United States; A Guide for Identifying and Delineating Hydric Soils, Version 9.0, 2024.
Situated close to the peak (~1067 m. elev.) on the plateau next to the road. It has a very deep organic layer of peat (on solifluction deposits) - the consistently cold and wet anaerobic soil conditions of this perched area does not favour organic breakdown.
The story:
The Bailey series consists of very deep, well drained soils formed in colluvium derived from rhyolite and tuff with loess influence. Bailey soils are on canyon walls and have slopes of 4 to 80 percent. The mean annual precipitation is about 430 mm and the mean annual air temperature is about 7.5 degrees C.
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Calcic Haploxerolls
USE AND VEGETATION:
Major uses: rangeland and wildlife habitat
Dominant native vegetation: Mountain big sagebrush, bluebunch wheatgrass, Idaho fescue, mountain brome, arrowleaf balsamroot
DISTRIBUTION AND EXTENT:
Distribution: Southeastern Idaho and Western Wyoming, MLRA 13
Extent: the series is not extensive
For additional information about Idaho soils, please visit:
storymaps.arcgis.com/stories/97d01af9d4554b9097cb0a477e04...
For a detailed description, visit:
soilseries.sc.egov.usda.gov/OSD_Docs/B/BAILEY.html
For acreage and geographic distribution, visit:
Scientists from PNNL present the fourth and final lesson in their after-school series at Sagebrush Montessori School in Richland, WA. In this lesson, students learned about mushrooms.
Terms of Use: Our images are freely and publicly available for use with the credit line, "Andrea Starr | Pacific Northwest National Laboratory"; Please use provided caption information for use in appropriate context.
Densic materials.—A diagnostic soil characteristic consisting of relatively unaltered, noncemented (i.e., they slake in water), compact, and root-restrictive soil materials. The compaction is non-pedogenic and may be geologic or human induced. Densic materials commonly consist of earthy materials such as dense glacial till or volcanic mudflows, but they include mechanically compacted materials such as those in a plow pan or heavily trafficked area. Noncemented rock such as highly weathered, unconsolidated sandstone can also be considered densic material. Densic materials, by definition, cannot also meet the criteria for any other diagnostic horizon or characteristic. Their definition was included in the 7th edition of the Keys to Soil Taxonomy (1996) in part to accommodate the decision to not recognize fragipans in relatively unaltered dense glacial till. See paralithic materials and slake.
Figure 35.—Examples of soils with densic materials.
Left photo: Soil profile of Mitchellbay soil (fine-loamy, mixed, superactive, mesic Aquultic Haploxeralfs). The Mitchellbay series consists of moderately deep (to densic materials) somewhat poorly drained soils formed in glacial drift over glaciomarine deposits. Mitchellbay soils are in valleys and on glacial drift plains and have slopes of 0 to 25 percent.
Middle photo: Soil profile of Poquonock soil (mixed, mesic Typic Udipsamments). The Poquonock series consists of very deep, well drained, soils formed in sandy eolian or glaciofluvial material over loamy or sandy lodgement till on uplands. They are moderately deep to a densic contact and very deep to bedrock. They are nearly level through moderately steep soils on till plains, moraines and drumlins.
Right photo: Soil profile of Woodbridge soil (coarse-loamy, mixed, active, mesic Aquic Dystrudepts). The Woodbridge series consists of moderately well drained loamy soils formed in lodgment till. They are very deep to bedrock and moderately deep to a densic contact. They are nearly level to moderately steep soils on hills, drumlins, till plains, and ground moraines.
A soil color map of the continental US composed of 750 soil profiles from around the country. [SCREENSHOT]
A soil profile of Buncombe soils from Polk County, NC. For more information about the soils of Polk County, visit: Soil Survey of Polk County, North Carolina.
The Buncombe series consists of very deep, excessively drained sandy soils on nearly level to gently sloping flood plains in the Piedmont and Coastal Plain. They formed in sandy alluvium washed from soils formed in residuum from schist, gneiss, granite, phyllite, and other metamorphic and igneous rocks of the Piedmont. Slopes range from 0 to 6 percent.
TAXONOMIC CLASS: Mixed, thermic Typic Udipsamments
RANGE IN CHARACTERISTS: Depth to hard bedrock is more than 10 feet. Layers of gravel and cobbles are in the substrata of some pedons below a depth of 40 inches. Few to many mica flakes are present throughout the profile. Reaction ranges from very strongly acid to slightly acid. The A, Bw and C horizons to a depth of 40 inches are sand, loamy sand, or loamy fine sand. In addition, The C horizon may be fine sand within a depth of 40 inches. Below a depth of 40 inches, textures of the C horizon range from sand to loam or are stratified.
DRAINAGE AND PERMEABILITY: Excessively drained; very slow runoff; rapid and very rapid permeability.
USE AND VEGETATION: More than one-half of the soil has been cleared and is used for growing pasture or crops. A few areas are in loblolly, longleaf, or shortleaf pines. Natural vegetation consists mainly of hardwoods such as sweetgum, oaks, birch, elm, ash, hickory, yellow- poplar, sycamore, and willow
trees.
DISTRIBUTION AND EXTENT: Alabama, Georgia, North Carolina, South Carolina, and Virginia. The series is of moderate extent.
The Environment Agency-Abu Dhabi (EAD) has completed a $6.5 million (USD) contract with an Australian firm (GRM International) for a soil survey, which involves satellite images, soil analyses and land mapping.
The contract was signed between by Majid Al Mansouri, EAD Secretary-General and Dr Stewart Routledge, Middle East Director of GRM International of Australia. The project will be carried out in partnership with the Dubai-based International Centre for Biosaline Agriculture (ICBA), with which EAD signed an agreement of cooperation. The ICBA will provide technical support during the project, which is aimed at providing baseline information to better understand, manage, conserve and sustain the emirate's soil resources.
The project was approved by the Executive Committee of Abu Dhabi last year. The survey, according to the agency, will assist decision-makers in future land use planning on scientific grounds. "It will also provide an on-the-ground, scientific inventory of soil resources, help in developing a soil database using Geographic Information Systems (GIS), prepare a soil survey report and soil and land use maps and build the capacity of UAE nationals," Al Mansouri said after signing the agreement.
Unplanned expansion and developmental activities have caused the deterioration of soil resources. Under the project, the soil, mainly in the Eastern Region of Abu Dhabi, will be mapped and classified using the latest satellite images, and norms and standards of the United States Department of Agriculture.
"Planners, engineers and developers will be able to use the soil survey maps and data to evaluate soil for engineering purposes, select sites for residence, agriculture, industry, construction, routes for highways," said Majid Al Mansouri, EAD Secretary-General.
His Highness (center) Sheikh Mohammed bin Zayed Al Nahyan, Crown Prince of Abu Dhabi launches the International Water Summit as part of a sustainability vision aimed at ensuring the welfare of the UAE – and the world.
(L) Majed Ali Al Mansouri
(C) Sheikh Mohammed bin Zayed Al Nahyan
(R) Razan Khalifa Al Mubarak
Photo courtesy of EAD-Environment Agency - Abu Dhabi. www.ead.gov.ae/
en.wikipedia.org/wiki/Environment_Agency_Abu_Dhabi
Established in 1996, the Environment Agency – Abu Dhabi (EAD) is committed to protecting and enhancing air quality, groundwater as well as the biodiversity of our desert and marine ecosystem. By partnering with other government entities, the private sector, NGOs and global environmental agencies, we embrace international best practice, innovation and hard work to institute effective policy measures. We seek to raise environmental awareness, facilitate sustainable development and ensure environmental issues remain one of the top priorities of our national agenda.
A representative soil profile of the Armour soil series. (Soil Survey of Cannon County, Tennessee; by By Jerry L. Prater, Natural Resources Conservation Service)
The Armour series consists of very deep well drained soils on stream terraces, foot slopes, and valley floors. These soils formed in old alluvium, valley fill, or in alluvium and the underlying residuum of limestone. Slopes range 0 to 20 percent.
TAXONOMIC CLASS: Fine-silty, mixed, active, thermic Ultic Hapludalfs
Solum thickness ranges from 40 to more than 80 inches. Depth to limestone bedrock is greater than 5 feet. Reaction is moderately acid or strongly acid except the surface layer is less acid where limed. Fragments of gravel or chert range from 0 to 10 percent in the upper 40 inches. The fragments range up to about 3 inches in diameter. Below 40 inches the fragment content is dominantly 0 to 35 percent, but ranges to 60 percent.
USE AND VEGETATION: Most of the areas are cleared and used for pasture, hay, small grain, tobacco, and corn. The native vegetation was mixed hardwoods including oaks, hickory, elm, hackberry, maple, beech, black walnut, ash, locust, yellow-poplar, and red cedar.
DISTRIBUTION AND EXTENT: The Nashville Basin and Highland Rim in Tennessee and the inner bluegrass region of Kentucky. The series is of moderate extent.
For additional information about the survey area, visit:
www.nrcs.usda.gov/Internet/FSE_MANUSCRIPTS/tennessee/cann...
For a detailed soil description, visit:
soilseries.sc.egov.usda.gov/OSD_Docs/A/ARMOUR.html
For acreage and geographic distribution, visit:
A soil profile of Barnwell loamy coarse sand in Lee County, South Carolina.
TAXONOMIC CLASS: Fine-loamy, kaolinitic, thermic Typic Kanhapludults
Depth Class: Very deep
Drainage Class (Agricultural): Well drained
Internal Free Water Occurrence: Deep and transitory
Flooding Frequency and Duration: None
Ponding Frequency and Duration: None
Index Surface Runoff: Negligible to high
Permeability: Moderately slow to slow
Shrink-swell potential: Low
Landscape: Middle and upper coastal plain
Landform: Uplands
Hillslope Profile Position: Summits, shoulders, backslopes
Geomorphic Component: Interfluves, side slopes
Parent Material: Marine deposits
Slope: 2 to 15 percent
Depth to contrasting soil material (lithologic discontinuity): 35 to more than 80 inches
Depth to densic materials: 40 to more than 60 inches
Ironstone and plinthite nodules: less than 5 percent throughout
USE AND VEGETATION: Where cultivated--vegetable crops, wheat, soybean, cotton, and corn. Where wooded--mixed hardwoods and pines.
DISTRIBUTION AND EXTENT: Southern Coastal Plain in South Carolina, and possibly Virginia, North Carolina, Alabama, and Georgia with moderate extent.
For a detailed description, visit:
soilseries.sc.egov.usda.gov/OSD_Docs/B/BARNWELL.html
For acreage and geographic distribution, visit:
John A. Kelley is a soil scientist previously with the Natural Resources Conservation Service (NRCS), United States Department of Agriculture and Environment Agency of Abu Dhabi, UAE. John is a soil survey quality assurance expert and a specialist in soil mapping, soil classification, and correlation of soil survey projects. He has extensive experience in soil survey procedures and documentation including digital soil photography.
Soil survey quality assurance is the process of providing technical standards and guidelines, oversight and review, and training to ensure that soil survey products meet NCSS standards. Responsibility for ensuring the quality of soil survey products such as maps, descriptions, data, texts, photographs, etc., rests with the soil survey regional office (SSR).
Quality control and quality assurance are important at all levels in the preparation, publication, and update of a soil survey. Their purpose is to ensure that soil survey products are accurate and consistent, meet the objectives outlined in the memorandum of understanding or project plan, and satisfy the needs of the majority of soil survey users. Quality control and quality assurance activities also are carried out at other locations where soil survey products are developed, such as the National Soil Survey Center’s Kellogg Soil Survey Laboratory (KSSL) and the National Geospatial Center of Excellence (NGCE).
For more information about Describing and Sampling soils, visit;
www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052523...
For more information about Soil Taxonomy, visit;
The Al Maalla series is a very deep soil formed in sandy alluvial deposits that increase in gravel content with depth. (NE016) UAE.
Taxonomic classification: Typic Haplocalcids, sandy, mixed, hyperthermic
Diagnostic subsurface horizon described in this profile is: Calcic horizon 10 to 200 cm.
The particle-size control section has a weighted average of 25 to 50% very fine sand and finer. The pH (1:1) ranges from 7.0 to 8.6 throughout the profile. The EC (1:1) is generally less than 1.0 in all horizons, but it may be as high as 2.0 in some areas. A desert pavement of fine to medium gravel in many areas covers 5 to 25% of the soil surface. A 2B horizon with a significant increase in gravel is generally encountered between 65 and 200 cm. Accumulations of calcium carbonate are evident in the form of masses or concretions in some or all parts of the B horizon. The B and 2B horizons may be extremely weakly cemented to moderately cemented with carbonates. However, roots appear to be able to penetrate with a spacing of less than 10 cm. Some pedons lack cementation.
The A horizon is generally about 20 cm thick, but ranges from 5 to 25 cm. Hue is 7.5YR or 10YR, value is 5 to 7, and chroma is 3 or 4. Texture is fine sand, loamy fine sand, or fine sandy loam. Fine or medium gravel ranges from 0 to about 10% in the A horizon.
The B horizon has hue of 7.5YR or 10YR, value of 5 to 7, and chroma of 3 to 6. Texture is predominantly coarse sand, sand, fine sand, or loamy fine sand, including gravelly texture modifiers. Thin horizons of sandy loam or fine sandy loam occur in some pedons. Fine or medium gravel ranges from 0 to about 30% in the B horizon.
The 2B horizon has hue of 5YR, 7.5YR, or 10YR, value of 5 or 6, and chroma 3 to 6. It is gravelly to extremely gravelly sand, loamy sand, or coarse sand. Gravel content ranges from 15 to 70%.
Depth Class: Moderately deep to soft bedrock
Drainage Class (Agricultural): Somewhat poorly drained
Internal Free Water Occurrence: Very shallow or shallow, common, very thin to thick
Flooding Frequency and Duration: None or very rare for brief periods
Ponding Frequency and Duration: None
Index Surface Runoff: Negligible to high
Saturated Hydraulic Conductivity: Moderately high to moderately low
Shrink-swell Potential: Low
Landscape: Piedmont uplands
Landform: Flats, depressions, sloughs, and drainageways
Geomorphic Component: Talf, dip, and rise
Hillslope Profile Position: None assigned
Parent Material: Residuum weathered from Carolina slate (dominantly argillite formed in sediments derived from fine-grained volcanic and metavolcanic rock)
Slope: 0 to 15 percent
TAXONOMIC CLASS: Fine-silty, siliceous, subactive, thermic Aeric Epiaquults
Depth to top of argillic horizon: 13 to 36 centimeters (about 5 to 14 inches)
Depth to base of argillic horizon: 45 to 96 centimeters (about 18 to 38 inches)
Depth to bedrock: 50 to 100 centimeters (20 to 40 inches) to soft bedrock and more than 100 centimeters (40 inches) to hard bedrock
Depth to seasonal high water table: 15 to 46 centimeters (about 6 to 18 inches) (perched) for 3 to 5 months (November to March)
Rock Fragment Content: 0 to 25 percent, by volume argillite paragravel or parachanners or quartz gravel in the A, E, and B horizons and 0 to 30 percent in the C horizon
Soil Reaction: Very strongly acid to moderately acid throughout, unless limed.
Effective Cation Exchange Capacity: 5 to 20 milliequivalents per 100 grams of soil in the A horizon; 3 to 10 in E and B horizons; and 5 to 15 in the C horizon
USE AND VEGETATION: Dominantly forested with cleared areas primarily in pasture and a very small acreage in cropland
DISTRIBUTION AND EXTENT: The slate belt of the Piedmont of North Carolina and possibly South Carolina with moderate extent.
For a detailed description, visit:
soilseries.sc.egov.usda.gov/OSD_Docs/B/BISCOE.html
For acreage and geographic distribution, visit:
Soil classification is the basis for agrotechnology transfer and for national or regional planning. Soils information is communicated through a common international system such as Soil Taxonomy. Using Soil Taxonomy will provide a strong basis for transferring information from soils in other parts of the world where important research results are available. This monograph summarizes and discusses the various rationale behind many of the concepts implicit in Soil Taxonomy.
These concepts and rationale were presented in a series of interviews by the late Dr. Guy D. Smith in 1980-81. The interviews covered by this monograph were held at Cornell University in 1980; by Dr. H. Eswaran in Ghent, Belgium in 1980; by Dr. M. Leamy in Ghent, Belgium in 1980; at the University of Minnesota in 1981; at Texas Tech University (not Texas A&M University) in 1980; in Maracay, Venezuela in 1981; and by Dr. J. Witty and Dr. R. Guthrie in Belgium in 1980. There is also the text of a lecture that Dr. Smith delivered at the Department of Soil Science, University of the West Indies on February 6, 1981.
A must read for any Soil Scientist. To view, print, or save a pdf copy visit Rationale for Concepts in Soil Taxonomy.
Note: The left side of the photo exhibits natural soil structure. The right side has been smoothed.
A representative soil profile of Grainola clay loam. (Soil Survey of Noble County, Oklahoma; by Gregory F. Scott, Troy L. Collier, Jim E. Henley, R. Dwaine Gelnar, and Karen B. Stevenson, Natural Resources Conservation Service)
The Grainola series consists of moderately deep, well drained soils that formed in material weathered from shale of Permian age. These soils are on summits and backslopes of low hills in the Central Rolling Red Prairies (MLRA 80A). Slope ranges from 1 to 25 percent. Mean annual air temperature is 16 degrees C (60 degrees F), and mean annual precipitation is 840 mm (33 in).
TAXONOMIC CLASS: Fine, mixed, active, thermic Udertic Haplustalfs
Depth to bedrock: 51 to 102 cm (20 to 40 in)
Parent material: noncemented soft siltstone or shale bedrock
Soil cracking: This soil has cracks within 125 cm (50 in)of the soil surface that are 5 mm (1 in) or more wide to a thickness of 30 cm (12 in) or more for some time in most years.
Depth to vertic features: pressure faces, slickensides or wedge-shaped aggregates in a layer 15 cm or more thick that has it upper boundary within 125 cm of the soil surface.
Linear extensibility of 6.0 cm or more between the soil surface and a depth of 100 cm (39 in) or a densic contact, whichever is shallower.
Coarse fragments: typically sandstone, sandstone cemented with hematite, and calcium carbonate concretions and nodules. Some areas have stones or boulders which cover 3 to 35 percent of the soil surface
USE AND VEGETATION: Nearly all used for range. Native vegetation is short and midgrass prairie.
DISTRIBUTION AND EXTENT: Oklahoma and Kansas; LRR H, Bluestem Hills (MLRA 76), and Central Rolling Red Prairies (MLRA 80A). The series is extensive. This series and OSD was originally set in Osage County in the Flint Hills in a limestone area. Rewrote OSD and moved location to accommodate the actual setting of series.
For additional information about the survey area, visit:
www.nrcs.usda.gov/Internet/FSE_MANUSCRIPTS/oklahoma/OK103...
For a detailed soil description, visit:
soilseries.sc.egov.usda.gov/OSD_Docs/G/GRAINOLA.html
For acreage and geographic distribution, visit:
The Ard series consists of moderately deep, well drained soils that formed in rhyolite residuum with loess influence. Ard soils are on mountain slopes and loess hills and have slopes of 4 to 12 percent.
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive Calcic Haplocryolls
Mollic epipedon thickness: 25 to 40 cm
Depth to bedrock: 50 to 100 cm
Depth to the calcic horizon (2Bk horizon): 25 to 40 cm
Particle size control section rock fragments: 0 to 35 percent
Particle size control section total clay: 7 to 18 percent
Reaction: neutral to strongly alkaline
Soil moisture regime: xeric, dry for 45to 60 consecutive days
Mean annual soil temperature: 3.9 to 7.2 degrees C. (cryic soil temperature regime)
Mean summer soil temperature: 10.0 to 15.0 degrees C.
USE AND VEGETATION:
Major uses: Non-irrigated winter and spring wheat, barley, and rangeland
Dominant native vegetation: mountain big sagebrush, Idaho fescue, bluebunch wheatgrass, tapertip hawksbeard
DISTRIBUTION AND EXTENT:
Distribution: Southeastern Idaho, MLRA 13
Extent: the series is not extensive
For additional information about Idaho soils, please visit:
storymaps.arcgis.com/stories/97d01af9d4554b9097cb0a477e04...
For a detailed description, visit:
soilseries.sc.egov.usda.gov/OSD_Docs/A/ARD.html
For acreage and geographic distribution, visit:
A representative soil profile of the Campbell series. The surface layer is very loose because of cultivation. The subsoil is silty clay loam that contains more clay as depth increases. Smooth excavation surfaces are visible below a depth of 80 centimeters. A buried clay soil occurs below 1 meter. (Supplement to the Soil Survey of Santa Clara Area, California, Western Part; Narratives written by William Reed, natural resources specialist, Natural Resources Conservation Service)
Landscape: A cultivated hayfield and an orange orchard in an area of Campbell soils along Zanker Road in San Jose, on the lower Guadalupe River-Coyote Creek flood plain. Newly constructed residential housing is in the background. Repeated annual flooding produced these silty soils, which are today protected by levees and upstream dams and drained by lowering the water table of the region. Most areas have been urbanized. Campbell soils are excellent for growing plants of all types.
The Campbell series consists of very deep, moderately well drained soils on floodplains and alluvial fans. These soils formed in alluvium derived from mixed rock sources. Slopes range from 0 to 2 percent. Mean annual precipitation is about 14 inches and the mean annual temperature is about 60 degrees F.
TAXONOMIC CLASS: Fine-silty, mixed, superactive, thermic Cumulic Haploxerolls
Note: Despite some wetness, mottles are too deep, below 20 inches, for an aquic suborder and chromas are too bright for an aquic extragrade. Major revision of description resulting from moving the type location during mapping of the Santa Clara Valley in 2006-2008 because the old type location was lost to urbanization.
The soils are developed in material of mixed mineralogy. Mean soil temperature is between 59 and 62 degrees F. The soils are moist from mid October until about June 15. The textural control section of 25 to 100 centimeters has clay content of 27 to 35 percent clay. Depth to the buried A horizon ranges from 30 to 100 centimeters. Fragments are gravel in size and range from 0 to 2 percent.
USE AND VEGETATION: Large areas have been urbanized and othere areas are used for row crops, truck crops, fruit orchards, pasture and hay. Native vegetation was grass-oak.
DISTRIBUTION AND EXTENT: Correlated only in Santa Clara County, California where the soil is moderately extensive. 14,000 acres.
For additional information about the survey area, visit:
www.nrcs.usda.gov/Internet/FSE_MANUSCRIPTS/california/san...
For a detailed soil description, visit:
soilseries.sc.egov.usda.gov/OSD_Docs/C/CAMPBELL.html
For acreage and geographic distribution, visit:
A Typic Haplocalcid from the interior of the UAE.
Note: The dark clumps on the soil surface are road apples from the camels. While the term “road apples” may conjure up a pleasant image of apple trees growing by the side of a bucolic country road, the truth is in fact much uglier. This term is used in regional American slang to refer to manure. Written evidence suggests that people started referring to horse dung as road apples around the mid 20th century.
Haplocalcids are the Calcids that have a calcic horizon with its upper boundary within 100 cm of the soil surface. These soils do not have a duripan or an argillic, natric, or petrocalcic horizon within 100 cm of the soil surface. Some of the soils have a cambic horizon above the calcic horizon. Haplocalcids are extensive.
Calcids are the Aridisols with calcium carbonate that was in the parent materials or was added as dust, or both. Precipitation is insufficient to leach or even move the carbonates to great depths. The upper boundary of the calcic or petrocalcic horizon is normally within 50 cm of the soil surface. If the soils are irrigated and cultivated, micronutrient deficiencies are normal. These soils are extensive in the western part of the United States and in other arid regions of the world.
For more information about describing soils, visit:
www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052523...
For additional information about soil classification using Soil Taxonomy, visit:
sites.google.com/site/dinpuithai/Home
For more information about soil classification using the UAE Keys to Soil Taxonomy, visit:
agrifs.ir/sites/default/files/United%20Arab%20Emirates%20...
Soil profile: Profile of a Culleoka soil. This soil has siltstone bedrock between depths of 50 and 100 centimeters. The bedrock limits the rooting depth and the amount of moisture available to plants. The Culleoka series consists of moderately deep, well drained, soils formed in colluvium or residuum from siltstone or interbedded shale, limestone, siltstone, and fine grained sandstone. (Soil Survey of Adair County, Kentucky; by Harry S. Evans, Natural Resources Conservation Service)
Landscape: Cabbage in an area of Culleoka-Weikert complex, 2 to 6 percent slopes. Culleoka soils form on steep upland hillsides and narrow ridgecrests with slopes ranging from 2 to 70 percent. Using a system of conservation tillage and planting cover crops reduce the runoff rate and help to minimize soil loss by erosion. Grassed waterways can be used in some areas to slow and direct the movement of water and reduce the hazard of erosion.
TAXONOMIC CLASS: Fine-loamy, mixed, active, mesic Ultic Hapludalfs
Thickness of the solum and depth to lithic bedrock of dominantly siltstone or fine grained sandstone is 20 to 40 inches. Content of flagstones and channers range from 0 to 35 percent in the A horizon, 10 to 35 percent in the B horizon, and 25 to 80 percent in the BC and C horizons. Reaction ranges from moderately to strongly acid in the solum and strongly to slightly acid in the substratum.
USE AND VEGETATION: Chiefly pasture and hay, with some tobacco, corn, and small grains. Native forest has oak, maple, black walnut, ash, hickory, beech, elm, hackberry, locust, Kentucky coffeetree, redbud, dogwood, and red cedar as the dominant species.
DISTRIBUTION AND EXTENT: The Bluegrass region of Kentucky, the outer Central Basin of Tennessee, Arkansas, Ohio, Pennsylvania, Virginia, and West Virginia. It is of moderate extent.
For additional information about the survey area, visit:
www.nrcs.usda.gov/Internet/FSE_MANUSCRIPTS/kentucky/KY001...
For a detailed soil description, visit:
soilseries.sc.egov.usda.gov/OSD_Docs/C/CULLEOKA.html
For acreage and geographic distribution, visit:
A representative soil profile of a Typic Petroargid from New Mexico. (Photo provided by USDA-NRCS-New Mexico.)
Typic Petroargids are the Petroargids that have a petrocalcic horizon that has its upper boundary within 150 cm of the soil surface. These soils do not have a soil moisture regime that borders on ustic or xeric. They occur in the southwestern part of the United States and in South Africa and Argentina.
Argids are the Aridisols that have an argillic or natric horizon but do not have a duripan or a gypsic, petrocalcic, petrogypsic, or salic horizon within 100 cm of the soil surface. The low water flux and high concentration of salts in many Aridisols hinder clay illuviation. The presence of an argillic horizon commonly is attributed to a moister paleoclimate, although there is evidence that clay illuviation occurred during the Holocene in arid soils. Where the soil moisture regime grades to ustic or xeric, evidence of clay translocation commonly is more readily established. Most of the Argids occur in North America. A few have been recognized in the deserts of North Africa or the Near East.
For additional information about U.S Soil Taxonomy, visit:
www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/survey/cla...
Soil profile: A representative soil profile of the Santa series. The Santa series consists of moderately well drained soils that are moderately deep to a fragipan.
Landscape: Santa soils are on undulating to rolling loess hills and plains and have slopes of 2 to 35 percent. These soils are used for timber production, hay and pasture with small areas of wheat, barley, and grass seed.
Santa soils formed in deep loess with a small amount of volcanic ash in the upper part. The mean annual precipitation is about 685mm and the mean annual temperature is about 6.1 degrees C.
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, frigid Vitrandic Fragixeralfs
Average annual soil temperature: 6.7 to 8 degrees C.
Soil moisture: Usually moist, dry for 45 to 65 consecutive days in mid and late summer.
Depth to fragipan: 50 to 100 cm
Volcanic ash influence: 18 to 50 cm
Estimated properties of the volcanic ash influenced layers:
Volcanic glass content 5 to 20 percent
Acid oxalate-extractable Al + Fe 0.4 to 1.0 percent
Moist bulk density 1.0 to 1.4 g/cc
An O horizon is present in some pedons.
USE AND VEGETATION: These soils are used for timber production, hay and pasture with small areas of wheat, barley, and grass seed. The potential natural vegetation is an overstory of grand fir, Douglas-fir, ponderosa pine, western larch, lodgepole pine and western white pine. Understory vegetation includes myrtle pachstima, bromegrass, bedstraw, lily-of-the-valley and meadowrue.
DISTRIBUTION AND EXTENT: Northern Idaho and northeastern Washington. MLRAs 9 and 43A. The series is of moderate extent.
For additional information about Idaho soils, please visit:
storymaps.arcgis.com/stories/97d01af9d4554b9097cb0a477e04...
For a detailed soil description, visit:
soilseries.sc.egov.usda.gov/OSD_Docs/S/SANTA.html
For acreage and geographic distribution, visit:
A picnic spot with a lake and mountain in the background, and oasis nearby. Located on the Al Ain - Abu Dhabi truck road, Zakher Lake (formerly called Zakher Pools) is a large lake mainly consisting of a spill water and ground water in the desert, 12 kilometers west of the base of Jebel Hafeet. As of December 2012, the lake is as big as ever. A new picnic-site complete with shaded picnic tables and (closed) mobile toilet-shacks have been erected in late November 2012.
Lake Zakher is a man-made lake in the United Arab Emirates, near the border with Oman. It was created from treated waste water that was released onto land, which pushed up groundwater levels and eventually resulted in the development of a lake. It is a great location for wildlife photography.
A representative soil profile of the San Joaquin soil series, the California State Soil.
The San Joaquin series consists of moderately deep to a duripan, well and moderately well drained soils that formed in alluvium derived from mixed but dominantly granitic rock sources. They are on undulating low terraces with slopes of 0 to 9 percent. The mean annual precipitation is about 15 inches and the mean annual temperature is about 61 degrees F.
TAXONOMIC CLASS: Fine, mixed, active, thermic Abruptic Durixeralfs
Depth to the duripan ranges from 20 to 40 inches. The mean annual soil temperature varies from 60 degrees to 64 degrees F and the soil temperature is not below 47 degrees F at any time. The soil, at depths of about 7 to 24 inches or directly above the duripan, is dry in all parts from June to November and is moist in some or all parts the rest of the year. Clay increases by more than 15 percent absolute.
USE AND VEGETATION: Cropland and livestock grazing; crops are small grains, irrigated pasture and rice; vineyards, fruit and nut crops.
DISTRIBUTION AND EXTENT: Eastern side of the Sacramento and San Joaquin Valleys. The soils are extensive in MLRA-17. This soil series is bordering on the Typic Durixeralf subgroup. The type location of this series has been moved to better reflect the central concept as historically mapped. (Textures from lab data reflect slightly different values than field estimates. NSSL S83CA-077-042.)
For additional information about the survey area, visit:
www.nrcs.usda.gov/Internet/FSE_MANUSCRIPTS/california/CA0...
For a detailed soil description, visit:
soilseries.sc.egov.usda.gov/OSD_Docs/S/SAN_JOAQUIN.html
For acreage and geographic distribution, visit:
A representative soil profile of Pullman clay loam, 0 to 1 percent slopes, showing minor accumulations of secondary carbonates at about 80 centimeters and a strong calcic horizon at about 135 centimeters. (Soil Survey of Deaf Smith County, Texas; by Thomas C. Byrd, Natural Resources Conservation Service)
The Pullman series consists of very deep, well drained, slowly permeable soils that formed in clayey eolian deposits from the Blackwater Draw Formation of Pleistocene age. These soils occur on nearly level to very gently sloping plains or playa slopes. Slope ranges from 0 to 3 percent. The mean annual precipitation is about 483 mm (19 in) and the mean annual temperature is about 16 degrees C (60 degrees F).
TAXONOMIC CLASS: Fine, mixed, superactive, thermic Torrertic Paleustolls
Soil moisture: An ustic moisture regime bordering on aridic. The soil moisture control section is dry in some or all parts for more than 180 but less than 220 days, cumulative, in normal years.
Mean annual soil temperature: 15 to 18 degrees C (59 to 64 degrees F).
Thickness of the mollic epipedon: 30 to 76 cm (12 to 30 in).
Linear extensibility of top 1 m (40 in): 6 to 9 cm.
Depth to secondary carbonates: 50 to 76 cm (20 to 30 in).
Depth to calcic horizon: 76 to 150 cm (30 to 60 in).
Solum thickness: more than 203 cm (80 in).
Particle-size control section:
Silicate clay content: 35 to 50 percent
Carbonate clay content: 0 to 3 percent
USE AND VEGETATION:
Mainly cultivated to irrigated and dryland cotton, corn, grain sorghum, and winter wheat. Climax vegetation in rangeland includes blue grama and buffalograss, with lesser amounts of vine-mesquite, western wheatgrass, galleta or tobosa, silver bluestem, wild alfalfa, and prairie clover. This soil has been correlated to the Deep Hardland (R077CY022TX) ecological site in MLRA-77C.
DISTRIBUTION AND EXTENT:
General area: Western Texas
Land Resource Region: H - Central Great Plains Winter Wheat and Range Region
MLRA 77C - Southern High Plains, Southern Part
Extent: Large. This is a benchmark soil.
A benchmark soil is one of large extent within one or more major land resource areas (MLRAs), one that holds a key position in the soil classification system, one for which there is a large amount of data, one that has special importance to one or more significant land uses, or one that is of significant ecological importance.
For additional information about the survey area, visit:
www.nrcs.usda.gov/Internet/FSE_MANUSCRIPTS/texas/TX117/0/...
For a detailed soil description, visit:
soilseries.sc.egov.usda.gov/OSD_Docs/P/PULLMAN.html
For acreage and geographic distribution, visit:
Soil profile: A representative soil profile of the Santa series. The Santa series consists of moderately well drained soils that are moderately deep to a fragipan. (Soil Survey of Spokane County, Washington; by Scott H. Bare, Natural Resources Conservation Service)
Landscape: Santa soils are on undulating to rolling loess hills and plains and have slopes of 2 to 35 percent. These soils are used for timber production, hay and pasture with small areas of wheat, barley, and grass seed.
Santa soils formed in deep loess with a small amount of volcanic ash in the upper part. The mean annual precipitation is about 685mm and the mean annual temperature is about 6.1 degrees C.
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, frigid Vitrandic Fragixeralfs
Average annual soil temperature: 6.7 to 8 degrees C.
Soil moisture: Usually moist, dry for 45 to 65 consecutive days in mid and late summer.
Depth to fragipan: 50 to 100 cm
Volcanic ash influence: 18 to 50 cm
Estimated properties of the volcanic ash influenced layers:
Volcanic glass content 5 to 20 percent
Acid oxalate-extractable Al + Fe 0.4 to 1.0 percent
Moist bulk density 1.0 to 1.4 g/cc
An O horizon is present in some pedons.
USE AND VEGETATION: These soils are used for timber production, hay and pasture with small areas of wheat, barley, and grass seed. The potential natural vegetation is an overstory of grand fir, Douglas-fir, ponderosa pine, western larch, lodgepole pine and western white pine. Understory vegetation includes myrtle pachstima, bromegrass, bedstraw, lily-of-the-valley and meadowrue.
DISTRIBUTION AND EXTENT: Northern Idaho and northeastern Washington. MLRAs 9 and 43A. The series is of moderate extent.
For additional information about the survey area, visit:
www.nrcs.usda.gov/Internet/FSE_MANUSCRIPTS/washington/spo...
For a detailed soil description, visit:
soilseries.sc.egov.usda.gov/OSD_Docs/S/SANTA.html
For acreage and geographic distribution, visit:
The Alpin series consists of very deep, excessively drained, moderately rapidly permeable soils on uplands and river terraces of the Coastal Plain. They formed in thick beds of sandy eolian or marine deposits. Depth to seasonal water table is more than 80 inches. Some low terraces flood occasionally for brief periods.
TAXONOMIC CLASS: Thermic, coated Lamellic Quartzipsamments (This pedon is marginal to a Psammentic Paleudult, Valdosta series)
Thickness of sand is 80 inches or more. Reaction ranges from very strongly acid to slightly acid throughout. Depth to lamellae ranges from 40 to 78 inches but most commonly is 50 to 70 inches. Cumulative thickness of lamellae ranges from 1 cm to 15 cm. Content of silt plus clay in the 10 to 40-inch control section ranges from 5 to 10 percent.
Many areas are planted to pine. Some small areas have been cleared and are used for tobacco, peanuts, watermelons, and tame pasture. The native vegetation consists of scattered slash pine and longleaf pine, turkey oak, post oak, blackjack oak, and bluejack oak. The understory is dominated by bluestem, low panicums, fringeleaf paspalum, and native annual forbs.
DISTRIBUTION AND EXTENT: Atlantic and Gulf Coastal Plain. The series is of large extent.
For a detailed description, visit:
soilseries.sc.egov.usda.gov/OSD_Docs/A/ALPIN.html
For acreage and geographic distribution, visit:
A representative soil profile of Bowie fine sandy loam. (Soil Survey of Shelby County, Texas; by Kirby Griffith, Natural Resources Conservation Service)
The Bowie series consists of very deep, well drained soils that formed in loamy Coastal Plain deposits on the Queen City, Reklaw, Cook Mountain, Sparta, Cockfield and Carrizo Sand Formations. These very gently sloping to moderately sloping soils are on interfluves. Slopes range from 1 to 8 percent but are dominantly 1 to 5 percent. Mean annual air temperature is about 18 degrees C (65 degrees F), and mean annual precipitation is about 1270 mm (50 in).
TAXONOMIC CLASS: Fine-loamy, siliceous, semiactive, thermic Plinthic Paleudults
Soil Moisture: An udic soil moisture regime. The soil moisture control section is not dry in any part for more than 90 days in normal years.
Mean annual soil temperature: 16 to 21 degrees C (61 to 70 degrees F)
Depth to argillic horizon: 5 to 51 cm (2 to 20 in)
Thickness of solum: 152 to more than 203 cm (60 to more than 80 in)
Depth to redox concentrations: 25 cm to 173 cm (10 to 68 in)
Depth to episaturation: 107 to 152 cm (42 to 60 in)
Depth to albic materials: 114 to 173 cm (45 to 68 in)
Particle-size control section (weighted average)
Clay content in the Control Section: 18 to 30 percent
Silt plus very fine sand : 30 to 60 percent
Very fine sand and fragments up to 8 cm (3 in) in diameter: 15 to 45 percent of sand fraction
Cation Exchage Capacity: 6.0 to 18.0 meg/100 gram of soil.
USE AND VEGETATION: The principal use is for pasture and forest. Some areas are used for growing corn, peanuts, sweet potatoes, peaches, watermelons and other vegetables or fruit crops. Pasture is mainly bermudagrass or bahiagrass. Forests consist of loblolly and shortleaf pines, sweetgum, red oak, and hickory trees with tall and midgrasses.
DISTRIBUTION AND EXTENT: Texas, Arkansas, and Louisiana. Land Resource Region P, MLRA 133A and 133B; The series is of large extent.
For additional information about the survey area, visit:
www.nrcs.usda.gov/Internet/FSE_MANUSCRIPTS/texas/TX419/0/...
For a detailed soil description, visit:
soilseries.sc.egov.usda.gov/OSD_Docs/B/BOWIE.html
For acreage and geographic distribution, visit:
A representative soil profile of the Aille series in an area of improved grassland from Ireland. These soils formed in coarse loamy material over limestone bedrock.
For detailed information about this soil, visit;
gis.teagasc.ie/soils/rep_profile_sheet.php?series_code=11...
For information about the soil series of Ireland, visit;
gis.teagasc.ie/soils/soilguide.php
In the Irish soil classification system these soils are Gleyic Brown Earths (relatively young soils or soils with little profile development). These soils display gleyic features due to the presence of a shallow fluctuating groundwater table.
For more information about describing and classifying soils using the Irish Soils Classification System, visit:
gis.teagasc.ie/soils/downloads/SIS_Final_Technical_Report...
The dense, red layer underlying the plinthic zone (Btv) is referred to by local soil scientists as the "brick" due to its brick-like characteristics (area below wavy boundary).
This zone is particularity perplexing. Determining the correct horizon nomenclature requires numerous considerations. B horizons must have evidence of pedogenesis. This would commonly include soil structure, development of plinthite, and/or translocation of clay in the form of clay films or clay bridging or formation of other diagnostic features. Soil structure in this layer (if observable) is very weak and very to extremely coarse. Weak coarse subangular blocky aggregates can rarely be identified and lack clearly formed ped faces. Plinthite is absent or is less than 5 percent (by volume). Ironstone, if present, is most commonly in an elongated cylindrical pattern encompassing old root channels/animal borrowings, rarely as ironstone concretions. Clay films in the traditional form are very rare or absent; however, thick continuous clay flows or coatings greater than 1mm thick are common in old abandoned root channels or along randomly spaced internal vertical cracks. Clay bridging of sand grains is common, but weakly expressed. If pedogenesis has been concluded, the layer may also have fragic soil properties.
Fragic soil properties (FSPs) are principally based on slaking characteristics (non-cemented material) as well as field criteria including evidence of pedogenesis, a rupture resistance class that is firm or firmer, brittle manner of failure, and the ability to restrict the entry of roots. Note: Although thought to characteristically have prismatic structure, a fragipan horizon may be dominantly massive. The properties required for FSPs are common and observable in this layer.
With the striking visual difference between the overlying Btv horizon and the brick layer, is there a lithologic discontinuity? "Not everyone agrees on the degree of change required for a lithologic discontinuity. "No attempt is made to quantify lithologic discontinuities" (KST). Abrupt changes in color that are not the result of pedogenic processes can be used as indicators of a discontinuity.
Although the transition between the plinthic horizon (Btv) and the brick layer (2BCtx) is most commonly abrupt and very striking, it has been observed to be more gradual is other pedons. This is thought to be the result of the intensity of the flow patterns at the time of deposition or subsequent erosion on the base layer prior to secondary deposition. The brick layer is considered to be of a much greater age than the overlying materials in which the contemporary pedon formed. If the abrupt transition is absent, the materials may be of a single origin to the depth observed.
If the exposure is naturally eroding, the brick layer almost always forms a ledge at the contact with the overlying plinthic horizon.
A plinthic horizon contains a significant amount of plinthite. If the horizon constitutes a "continuous phase", zones that roots can enter are more than 10cm apart and plinthite makes up 50 percent or more of the volume of the horizon (proposed). Plinthite (Gr. plinthos, brick) is an iron-rich, humus-poor mixture of clay with quartz and other highly weathered minerals. It commonly occurs as reddish redox concentrations in a layer that has a polygonal (irregular), platy (lenticular), or reticulate (blocky) pattern.
Plinthite irreversibly hardens upon exposure to repeated wetting and drying, especially if exposed to heat from the sun. Other morphologically similar iron-rich materials that do not progressively harden upon repeated wetting and drying are not considered plinthite. The horizon in which plinthite occurs commonly has 2.5 percent (by mass) or more citrate dithionite extractable iron in the fine-earth fraction and a ratio between acid oxalate extractable Fe and citrate-dithionite extractable Fe of less than 0.10.
Soils that classify as Plinthudults have one or more horizons within 150 cm of the mineral soil surface in which plinthite either forms a continuous phase or constitutes one-half or more of the volume.
For more information about a plinthic horizon, visit;
www.researchgate.net/publication/242649722_Rationale_for_...
or;
www.sciencedirect.com/science/article/pii/S00167061220043...
For more information about describing and sampling soils, visit:
www.nrcs.usda.gov/resources/guides-and-instructions/field...
or Chapter 3 of the Soil Survey manual:
www.nrcs.usda.gov/sites/default/files/2022-09/The-Soil-Su...
For additional information on "How to Use the Field Book for Describing and Sampling Soils" (video reference), visit:
www.youtube.com/watch?v=e_hQaXV7MpM
For additional information about soil classification using USDA-NRCS Soil Taxonomy, visit:
www.nrcs.usda.gov/resources/guides-and-instructions/keys-...
or;
www.nrcs.usda.gov/resources/guides-and-instructions/soil-...
Soil profile: A representative soil profile of Bonneau loamy sand. Bonneau soils have thick sandy surface layers underlain by a loamy moderately permeable subsoil. In the winter months (December through March) they have a seasonal high water table at a depth below 100 centimeters.
Landscape: A broad area prepared for use as a wildlife food plot in an area of Bonneau loamy sand, 0 to 5 percent slopes. Soil Survey of Stewart County, Georgia; by Kenneth W. Monroe, Natural Resources Conservation Service)
TAXONOMIC CLASS: Loamy, siliceous, subactive, thermic Arenic Paleudults
Depth Class: Very deep
Drainage Class (Agricultural): Well drained
Internal Free Water Occurrence: Deep, common
Flooding Frequency and Duration: None
Ponding Frequency and Duration: None
Index Surface Runoff: Negligible to medium
Permeability: Moderate
Shrink-swell potential: Low
Landscape: Lower, middle, and upper coastal plain
Landform: Marine terraces, uplands
Hillslope Profile Position: Summits, shoulders, backslopes
Geomorphic Component: Interfluves, side slopes
Parent Material: Marine deposits, fluviomarine deposits
Slope: 0 to 12 percent
USE AND VEGETATION: Where cultivated--growing cotton, corn, soybeans, small grain, pasture grasses, and tobacco. Where wooded--mixed hardwood and pine, including longleaf and loblolly pine, white, red, turkey, and post oak, dogwood, and hickory.
DISTRIBUTION AND EXTENT: Coastal Plain of Alabama, Florida, Georgia, North Carolina, South Carolina, and Virginia, with moderate extent.
For additional information about the survey area, visit:
www.nrcs.usda.gov/Internet/FSE_MANUSCRIPTS/georgia/stewar...
For a detailed soil description, visit:
soilseries.sc.egov.usda.gov/OSD_Docs/B/BONNEAU.html
For acreage and geographic distribution, visit:
A representative soil profile of a sandy, siliceous, isohyperthermic Entic Grossarenic Alorthod
(Photo and comments courtesy of Stan Buol, NCSU.)
This profile was photographed in the state of Loreto, Peru SA. The site is in the Amazon River basin. A thin spodic horizon slightly above 200 cm, but dipping to below 200 cm to the right of the tape barely qualifies this profile as a Spodosol. Such soils are frequently associated with Quartzipsamments that have no spodic horizon or a spodic horizon that is deeper than 200 cm.
Spodosols and associated Quartzipsamments have been estimated to occupy as much as 10 percent of the Amazon basin with the greatest concentration in the Rio Negro basin watershed in Brazil. However, there are rather isolated occurrences where sandy textured parent material presumably deposited at point bar locations of the meandering river systems have change course throughout the western part of the Amazon basin.
Tropical forests vegetates such sites although vegetation is less dense than surrounding areas with finer textured soils. Indigenous people seldom select such sites for slash and burn cultivation and once cleared, burned and abandoned they are extremely slow to again vegetate. The presence of such sites can often be located because the white sandy material is dug and deposited in an attempt to improve trafficking in the wetter spots of the primitive roadways. The sand is the coarsest material locally available in the area that is devoid of gravel deposits. Coffee colored (black water) streams also are indicators of such soils in their watersheds.
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Entic Grossarenic Alorthods are the Alorthods that have a sandy or sandy-skeletal particle-size class from the mineral soil surface to the top of a spodic horizon at a depth of 125 cm or more and have less than 3.0 percent organic carbon in the upper 2 cm of the spodic horizon. These soils are not saturated with water for 20 or more consecutive days or 30 or more cumulative days in normal years and do not have an argillic or kandic horizon. They are common in the southeastern part of the United States. Most do or did support hardwood vegetation, but some have been cleared for crop production.
Alorthods are the Orthods that have accumulations of aluminum that are relatively high compared to the accumulations of iron. These soils formed predominantly in sandy deposits. The soils have low accumulations of iron either because of intensive leaching or because of parent materials that are low in iron. Alorthods normally have a thick albic horizon and an ochric epipedon. They are more common in areas of warm climates than in cool environments. In the United States, they occur mainly in the Southeast.
Orthods are the relatively freely drained Spodosols that have a horizon of accumulation containing aluminum, or aluminum and iron, and organic carbon. These are the most common Spodosols in the northern parts of Europe and in the United States. They formed predominantly in coarse, acid Pleistocene or Holocene deposits under a mostly coniferous forest vegetation. If undisturbed, Orthods normally have an O horizon, an albic horizon, and a spodic horizon and may have a fragipan. Some of these soils, however, have been mixed by the roots of falling trees or by animals and have a very thin albic horizon or no albic horizon.
For more information about describing soils, visit:
www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052523...
For additional information about soil classification using Soil Taxonomy, visit:
DEPTH CLASS: Very deep
DRAINAGE CLASS: Moderately well drained
PERMEABILITY: Moderate
SURFACE RUNOFF: Slow to medium
PARENT MATERIAL: Sandy marine and old alluvial sediments
SLOPE: 0 to 30 percent
TAXONOMIC CLASS: Fine-loamy, mixed, active, mesic Aquic Hapludults
RANGE IN CHARACTERISTICS:
Solum Thickness: 24 to 45 inches
Depth to Bedrock: Greater than 60 inches
Depth to Seasonal High Water Table: 18 to 42 inches, January to April
Rock Fragments: 0 to 15 percent, by volume in the A, E, and B horizon and 0 to 20 in the C horizon, mostly quartz pebbles
Soil Reaction: Extremely acid to strongly acid, throughout the profile, unless limed
USE: Most of the areas are used for crops including corn, soybeans, small grains, hay, and pasture.
VEGETATION: Native vegetation is oak and hardwoods with some Virginia pine. Loblolly pine occur in the southern part of the series range.
DISTRIBUTION: New Jersey, Delaware, Maryland, the District of Columbia, and the eastern part of Virginia and Pennsylvania. EXTENT: Large, over 250,000 acres
SERIES ESTABLISHED: Sussex County, Delaware, 1920
For more information about the survey area, visit:
www.nrcs.usda.gov/Internet/FSE_MANUSCRIPTS/delaware/susse...
For a detailed description, visit:
soilseries.sc.egov.usda.gov/OSD_Docs/W/WOODSTOWN.html
For acreage and geographic distribution, visit:
A Hemi-Orthic Histosols and landscape. These soils mainly distribute in Sanjiang Plain, Songhuajiang-liaohe Plain, and western Jilin Plain, as well as in gentle and broad valleys in low mountain and hilly areas in Wanda Mountain, Zhangguangcai Mountain, foothill of Changbaishan Mountain, and north-eastern Liaoning Province. Owing to poor drainage and seasonal waterlogging on ground surface, profiles of this soil are mostly saturated. Vegetation in areas concerned is composed of Cyperus rotundus, Deyeuxia langsdorffii, and Carex spp. In recent years, due to the building of water conservancy projects and increased developing of paddy field, the coverage of rice culture has been increasing year by year. Hemi-Orthic Histosols are mostly characterized by dominating hemic material in their surface tier, thicker profile and fragile weakly developed prismatic-blocky structure. (Photos and notes courtesy of China Soils Museum, Guangdong Institute of World Soil Resources; with revision.)
In Chinese Soil Taxonomy, Histosols have high amounts of organic matter accumulation under conditions of wetness and low temperature. In Soil Taxonomy these soils are mostly Histosols.
For additional information about this soil and the Soils Museum, visit:
www.giwsr.com/en/article/index/172
For additional information about Soil Taxonomy, visit:
A representative soil profile of the Awatere series from New Zealand. (Photo provided by NZ Soils.co.nz and Waikato Regional Council.) For more information about New Zealand soils, visit;
Awatere soils from 0 - 15 cm; Dark greyish brown gravelly sandy loam, weakly pedal, coarse blocky macrofabric. In the New Zealand Soil Classification system these soils are Typic Fluvial Recent Soils. For more information about the New Zealand Soil Classification system, visit;
soils.landcareresearch.co.nz/describing-soils/nzsc/
In U.S. Soil Taxonomy, these soils are Typic Ustifluvents. Ustifluvents are the Fluvents that have an ustic moisture regime and a temperature regime warmer than cryic. These soils are on flood plains along rivers and streams in areas of middle or low latitudes. Flooding can occur in any season but is most common in summer in the middle latitudes and during the rainy season in the Tropics. A few of the soils are flooded regularly in summer because of melting snow in high mountains, even though the summer is rainless.
Fluvents are mostly brownish to reddish soils that formed in recent water-deposited sediments, mainly on flood plains, fans, and deltas of rivers and small streams but not in backswamps where drainage is poor. The age of the sediments in humid regions commonly is a few years or decades or a very few hundred years. In arid regions it may be somewhat more. Many Fluvents are frequently flooded unless they are protected by dams or levees. Stratification of the materials is normal. Most of the alluvial sediments are derived from eroding soils or streambanks and contain an appreciable amount of organic carbon, which is mainly in the clay fraction. Strata of clayey or loamy materials commonly have more organic carbon than the overlying more sandy strata. Thus, the percentage of organic carbon of Holocene age decreases irregularly with increasing depth if the materials are stratified.
If the texture is homogeneous, the content of organic carbon decreases regularly with increasing depth. Because the deposits generally are loamy and recent, however, the percentage of carbon in the deep layers is higher than in soils that formed in parent materials other than alluvium.
For additional information about U.S. Soil Taxonomy, visit:
www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/survey/cla...
Scientists from PNNL present the fourth and final lesson in their after-school series at Sagebrush Montessori School in Richland, WA. In this lesson, students learned about mushrooms.
Terms of Use: Our images are freely and publicly available for use with the credit line, "Andrea Starr | Pacific Northwest National Laboratory"; Please use provided caption information for use in appropriate context.
A soil profile of Buncombe soils from Cleveland County, NC. For more information about the soils of Cleveland County, visit: Soil Survey of Cleveland County, North Carolina.
The Buncombe series consists of very deep, excessively drained sandy soils on nearly level to gently sloping flood plains in the Piedmont and Coastal Plain. They formed in sandy alluvium washed from soils formed in residuum from schist, gneiss, granite, phyllite, and other metamorphic and igneous rocks of the Piedmont. Slopes range from 0 to 6 percent.
TAXONOMIC CLASS: Mixed, thermic Typic Udipsamments
RANGE IN CHARACTERISTS: Depth to hard bedrock is more than 10 feet. Layers of gravel and cobbles are in the substrata of some pedons below a depth of 40 inches. Few to many mica flakes are present throughout the profile. Reaction ranges from very strongly acid to slightly acid. The A, Bw and C horizons to a depth of 40 inches are sand, loamy sand, or loamy fine sand. In addition, The C horizon may be fine sand within a depth of 40 inches. Below a depth of 40 inches, textures of the C horizon range from sand to loam or are stratified.
DRAINAGE AND PERMEABILITY: Excessively drained; very slow runoff; rapid and very rapid permeability.
USE AND VEGETATION: More than one-half of the soil has been cleared and is used for growing pasture or crops. A few areas are in loblolly, longleaf, or shortleaf pines. Natural vegetation consists mainly of hardwoods such as sweetgum, oaks, birch, elm, ash, hickory, yellow- poplar, sycamore, and willow
trees.
DISTRIBUTION AND EXTENT: Alabama, Georgia, North Carolina, South Carolina, and Virginia. The series is of moderate extent.
The central concept of Histosols is that of soils forming in organic soil materials. The general rule is that a soil without permafrost is classified as a Histosol if half or more of the upper 80 cm is organic. A soil is also classified as a Histosol if the organic materials rest on rock or fill or partially fill voids in fragmental, cindery, or pumiceous materials. If the bulk density is very low, less than 0.1, three-fourths or more of the upper 80 cm must be organic.
In both the World Reference Base for Soil Resources (WRB) and the USDA soil taxonomy, a Histosol is a soil consisting primarily of organic materials. They are defined as having 40 centimetres (16 in) or more of organic soil material in the upper 80 centimetres (31 in). Organic soil material has an organic carbon content (by weight) of 12 to 18 percent, or more, depending on the clay content of the soil. These materials include muck (sapric soil material), mucky peat (hemic soil material), or peat (fibric soil material). Aquic conditions or artificial drainage are required.
Typically, Histosols have very low bulk density and are poorly drained because the organic matter holds water very well. Most are acidic and many are very deficient in major plant nutrients which are washed away in the consistently moist soil.
Histosols are known by various other names in other countries, such as peat or muck. In the Australian Soil Classification, Histosols are called Organosols.
Histosols form whenever organic matter forms at a more rapid rate than it is destroyed. This occurs because of restricted drainage precluding aerobic decomposition, and the remains of plants and animals remain within the soil. Thus, Histosols are very important ecologically because they, and Gelisols, store large quantities of organic carbon. If accumulation continues for a long enough period, coal forms.
Most Histosols occur in Canada, Scandinavia, the West Siberian Plain, Sumatra, Borneo and New Guinea. Smaller areas are found in other parts of Europe, the Russian Far East (chiefly in Khabarovsk Krai and Amur Oblast), Florida and other areas of permanent swampland. Fossil Histosols are known from the earliest extensive land vegetation in the Devonian.
Histosols are generally very difficult to cultivate because of the poor drainage and often low chemical fertility. However, Histosols formed on very recent glacial lands can often be very productive when drained and produce high-grade pasture for dairying or beef cattle. They can sometimes be used for fruit if carefully managed, but there is a great risk of the organic matter becoming dry powder and eroding under the influence of drying winds. A tendency towards shrinkage and compaction is also evident with crops.
Like Gelisols, Histosols have greatly restricted use for civil engineering purposes because heavy structures tend to subside in the wet soil.
SOIL TAXONOMY
For more information about the U.S. Soil Classification System and to view or download "Soil Taxonomy, 2nd Edition, 1999." click HERE.
To download or order a hard copy of the latest version of "Soil Taxonomy, 2nd Edition, 1999", click HERE.
KEYS TO SOIL TAXONOMY
To view, print, or save a pdf copy of the Keys to Soil Taxonomy, 13th Edition, 2022, visit Keys to Soil Taxonomy
To download or order a hard copy of the latest version of Keys to Soil Taxonomy, 13th Edition, 2022, click HERE.
A three-day international conference on Soil Classification and Reclamation of Degraded Lands in Arid Environments (ICSC 2010) bringing together more than 130 scholars, researchers and experts was held in Abu Dhabi, UAE.
The conference, held under the patronage of H.H Sheikh Hamdan bin Zayed Al Nahyan, the Ruler’s Representative in the Western Region and Chairman of the Environment Agency – Abu Dhabi (EAD), aims to share information on land use and planning and discuss various issues in the field of soil classification and reclamation of degraded lands in arid environments.
On the first day of the conference, EAD will reveal the outcomes of the Abu Dhabi Soil Survey, which was initiated in 2006 and completed at the end of 2009.
The conference, which is organized by the Environment Agency – Abu Dhabi (EAD) and the International Center for Biosaline Agriculture (ICBA) from 17-19 May, 2010 in Abu Dhabi, UAE, was inaugurated by H.E. Majid Al Mansouri, EAD’s Secretary General.
In his opening speech, H.E Al Mansouri welcomed scientists, researchers and experts from 35 countries who have gathered to discuss various issues related to soil, land use and planning of agricultural expansion and sustainable use of natural resources.
"Our economy is rapidly growing and we have a hard desert environment, therefore we needed to identify the characteristics of soils in the various regions of the Emirate, for the development of land management and optimum economical use of those soils,” he said.
"EAD has undertaken an integrated project to survey the soils in the Emirate. This project has been brought to a successful conclusion after five years of studies, field surveys, and collection of soil samples, training and capacity-building culminating in the development of an integrated “Abu Dhabi Soil Information System” (ADSIS)”.
Dr Ahmed Al Masoum, ICBA’s Deputy Director General, said that "This conference is the beginning of a new era in soil research within the global scientific community."
"The Survey was the first of its kind in the Emirate and covered all areas of the Emirate of Abu Dhabi. Maps on current land use, vegetation and salinity were produced as well as detailed suitability maps for irrigated agriculture. The soil was mapped and classified using the latest satellite images, and norms and standards of the United States Department of Agriculture” he added.
Dr. Al Masoum added that the soil survey project was undertaken in two phases and involved the mapping and classification of the various types of soils in the Emirate of Abu Dhabi in two different scales. In the first phase the entire emirate was surveyed at a scale of 1:100,000, and in the second phase 400,000 hectares of land, evaluated as suitable for irrigated agriculture was surveyed at a scale of 1:25,000.
“We have uncovered valuable information for strategic planning for sustainable land use in the Emirate of Abu Dhabi, and particularly for the development of agriculture and sustainable management of natural resources,” he said.
The conference will feature six keynote speakers from Australia and India, Austria, Spain, Thailand and the United States, in addition to 130 speakers representing 35 countries from all over the world. Speakers will highlight Soil Survey and Classification Strategies and Use in Different Ecological Zones; Advances in Soil Salinity Mapping, Monitoring and Reclamation; Land Use Planning and Policy Implications; Use of Marginal Quality Water in Agriculture and Landscaping and Research and Development/Innovations in Soil Classification & Reclamation.
A workshop on how to use soil survey data in planning and policy making will be held on the sidelines of the conference.
www.researchgate.net/publication/259265194_Book_of_Abstra...
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Wisconsin State Soil: the Antigo series consists of very deep, well drained soils formed in 50 to 100 centimeters of loess or silty alluvium and in loamy alluvium and in the underlying stratified sandy outwash. (Soil Survey of Langlade County, Wisconsin; Michael J. Mitchell, Soil Conservation Service)
Antigo soils are on outwash plains, stream terraces, eskers, kames, glacial lake plains, and moraines. Slope ranges from 0 to 30 percent. Antigo soils are among the most extensive soils in Wisconsin. They occur on about 300,000 acres in the northern part of the State. They are very productive soils for corn, small grain, and hay. In some areas potatoes or snap beans are important crops. In 1983, the Wisconsin Legislature designated the Antigo series as the official State soil. The series was named after the city of Antigo, Wisconsin. Antigo soils are well-drained and formed in loess and loamy sediments over stratified sandy outwash. The average annual precipitation ranges from 28 to 33 inches, and the average annual air temperature ranges from 39 to 45 degrees F.
Most areas are cultivated. The principal crops are corn, small grains, and hay. In some places, potatoes and snap beans are important crops and some areas are pastured. Some areas are forested. The native vegetation is American basswood, sugar maple, yellow birch, white ash, big tooth aspen, quaking aspen, and black cherry.
DISTRIBUTION AND EXTENT:
Physiographic divisions--Interior Plains and Laurentian Upland
Physiographic Provinces--Central Lowland and Superior Upland
Physiographic section--Western Lake section
MLRAs--Wisconsin and Minnesota Thin Loess and Till, Northern Part (90A), Wisconsin and Minnesota Thin Loess and Till, Southern Part (90B), Central Minnesota Sandy Outwash (91A), Wisconsin and Minnesota Sandy Outwash (91B), and Superior Stony and Rocky Loamy Plains and Hills, Eastern Part (93B)
LRR K; northern Wisconsin and east-central Minnesota
Extent--large (over 250,000 acres)
TAXONOMIC CLASS: Coarse-loamy over sandy or sandy-skeletal, mixed, superactive, frigid Haplic Glossudalfs
Antigo soils have a glossic horizon (E/B or B/E horizons, or both). Horizonation has a wide range depending on the thickness of the silty mantle and the degree to which eluviation has occurred. Therefore, there can be E/B, B/E, 2E/B, or 2B/E horizons, singly or in combination, with or without Bt or 2Bt horizons.
For additional information about the survey area, visit:
www.nrcs.usda.gov/Internet/FSE_MANUSCRIPTS/wisconsin/lang...
For a detailed soil description, visit:
soilseries.sc.egov.usda.gov/OSD_Docs/A/ANTIGO.html
For acreage and geographic distribution, visit:
The Hegne series (a hydric soil) consists of very deep, poorly drained soils that formed in clayey calcareous lacustrine sediments on glacial lake plains. These soils have slow or very slow permeability. They have slopes of 0 to 2 percent.
Hydric soils are formed under conditions of saturation, flooding, or ponding long enough during the growing season to develop anaerobic conditions in the upper part (Federal Register, 1994). Most hydric soils exhibit characteristic morphologies that result from repeated periods of saturation or inundation that last more than a few days.
To download the latest version of "Field Indicators of Hydric Soils" and additional technical references, visit:
www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ref/?cid=s...
TAXONOMIC CLASS: Fine, smectitic, frigid Typic Calciaquerts
USE AND VEGETATION: Nearly all of these soils are cultivated. Principal crops are small grains and sugar beets. Native vegetation is tall grass prairie.
DISTRIBUTION AND EXTENT: Principally in the Red River Valley of northwestern Minnesota and eastern North Dakota, also in smaller glacial lake basins in western Minnesota and north-central North Dakota. These soils are extensive.
REMARKS: The classification of these soils is in question as to whether they should be in the Typic or Aeric subgroup of Calciaquerts. This needs further investigation. This series was previously classified in the Typic Calciaquolls subgroup.
For a detailed soil description, visit:
soilseries.sc.egov.usda.gov/OSD_Docs/H/HEGNE.html
For acreage and geographic distribution, visit:
Petroferric contact is a boundary between soil and a continuous layer of "indurated" material in which iron is an important cement and organic matter is either absent or present only in traces. However, is the material below the contact (the ironstone sheet) required to be indurated to have petroferric contact?
"Indurated" is generally used when referring to a class of rupture resistance. Rupture resistance is an estimate of the force required to rupture (break) an aggregate. The hardness of a fragment is significant where the rupture resistance class is strongly cemented or greater. Indurated is a class assigned to cemented materials that exhibit the strongest resistance to rupture.
The layer (below the contact) in this pedon from Lee County, SC, was cemented, but does not meet the criteria for an "indurated" rupture resistance class. Specimens tested failed by foot pressure under full body weight but could not be broken by moderate force between hands, indicating a "strongly cemented" rupture resistance class. Excavaton difficulty was very high, i.e., excavation by pick with over-the-head swing was moderately to markedly difficult.
Ironstone or other lithic materials are required to be strongly or more cemented (coherent), but not indurated. Does this pedon fall within a void in our soil classification system? Applying a strict application of the current description for petroferric materials, the pedon fails to meet the concept because it is not indurated. If a more liberal definition for petroferric materials is applied which includes strongly or more cemented materials it is within the conceptual model.
The "Keys to Soil Taxonomy, 13th Edition, p.37, Figure 3-24" describes this pedon as having a petroferric contact and an indurated ironstone sheet. This would lead one to assume the use of the term "indurated" as it applies with petroferric contact may not be the same as "indurated" when describing rupture resistance.
To date these soils have been observed in Louisiana. Mississippi, Georgia, South Carolina, and North Carolina. They are estimated to occur throughout the Coastal Plain of the southeastern US.
Additionally, if the hardpan layer was cemented, but less than strongly cemented, it would fail all current diagnostic subsurface horizon classifications. It would be easy to say this is an exception and not of critical importance; however, similar materials have been identified underlying plinthic soils in the Ceredo of Brazil.
[www.flickr.com/photos/jakelley/50556047286/in/album-72157..]
Nonpedogenic layers (such as bedrock) make a distinction for soft versus hard bedrock using a "para" prefix, i.e., "paralithic versus lithic contact. Using this same naming convention, is "parapetroferric contact" a reasonable consideration?
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For additional information about soil classification using Keys to Soil Taxonomy, 13th Edition, 2022, visit:
[www.nrcs.usda.gov/sites/default/files/2022-09/Keys-to-Soi...]
A petroferrric layer may be fractured if the average lateral distance between fractures is 10 cm or more. The fact that this ironstone layer contains little or no organic matter distinguishes it from a placic horizon and an indurated spodic horizon (ortstein), both of which contain organic matter.
The petroferric contact is generally recognized in some tropical and subtropical areas where layers of ironstone have formed in the soil as sesquioxides accumulated. In the Tropics, the ironstone is generally more or less vesicular (i.e., pockets or voids of softer material):
[www.flickr.com/photos/jakelley/50551133728/in/album-72157..].
This region lies in the south-west of the Emirate, adjacent to the border with Saudi Arabia. It constitutes linear dune fields of interlayered white carbonatic and red quartzite sands with minor exposure of Quaternary dunes and inter-dune formation.
The Rub' al Khali is the largest contiguous sand desert in the world, encompassing most of the southern third of the Arabian Peninsula. The desert covers some 650,000 square kilometres including parts of Saudi Arabia, Oman, the United Arab Emirates, and Yemen. It is part of the larger Arabian Desert. One very large pile of sand!!!
For more photos related to soils and landscapes visit:
Soil profile: A representative soil profile of an Inceptisol (bordrline Oxisol) from the Cerado physiographic region--a vast tropical savanna ecoregion of Brazil, particularly in the states of Goiás, Mato Grosso do Sul, Mato Grosso, Tocantins, Minas Gerais and the Federal District of Brazil. (Horizonation is by Brazil soil classification system.)
Landscape: Typical landscape and vegetation (rangeland in the foreground and eucalyptus plantation in the background) occurring on interfluve in Brazil.
Inceptisols are a soil order in USDA soil taxonomy. They form quickly through alteration of parent material. They are more developed than Entisols. The central concept of Inceptisols is that of soils that are of cool to very warm, humid and subhumid regions and that have a cambic horizon and an ochric epipedon. The order of Inceptisols includes a wide variety of soils. In some areas Inceptisols are soils with minimal development, while in other areas they are soils with diagnostic horizons that merely fail the criteria of the other soil orders. Inceptisols have many kinds of diagnostic horizons and epipedons. This pedon had few plinthite nodules and ironstone concretions in the subsoil.
Oxisols are a soil order in USDA soil taxonomy. Oxisols are weathered soils that are low in fertility. They are most common on the gentle slopes of geologically old surfaces in tropical and subtropical regions. Their profiles are distinctive because of a lack of obvious horizons. Their surface horizons are normally somewhat darker than the subsoil, but the transition of subsoil features is gradual. Some oxisols have been previously classified as laterite soils.
Inceptisol (Latossolos) and landscape BRAZIL--In the Brazil soil classification system, these Latossolos are highly weathered soils composed mostly of clay and weathering resistant sand particles. Clay silicates of low activity (kaolinite clays) or iron and aluminum oxide rich (haematite, goethite, gibbsite) are common. There are little noticeable horizonation differences. These are naturally very infertile soils, but, because of the ideal topography and physical conditions, some are being used for agricultural production. These soils do require fertilizers because of the ease of leaching of nutrients through the highly weathered soils.
For additional information about these soils, visit:
sites.google.com/site/soil350brazilsoilsla/soil-formation...
and...
For additional information about U.S. soil classification, visit:
www.nrcs.usda.gov/wps/portal/nrcs/main/soils/survey/class...