In the World Reference Base for Soil Resources and similar soil classification systems, a sapric is a subtype of a histosol where virtually all of the organic material has undergone sufficient decomposition to prevent the identification of plant parts.[1][2] Muck is a sapric soil that is naturally waterlogged or is artificially drained.

  • Muck
Used inWRB, USDA soil taxonomy, others
WRB codesa, HSsa
Parent materialOrganic matter


The soils are deep, dark colored, and friable, often underlain by marl, or marly clay.

World Reference Base

The World Reference Base for Soil Resources (WRB) defines "sapric" (sa) as a histosol having less than one-sixth (by volume) of the organic material consisting of recognizable plant tissue within 100 cm of the soil surface.[3]


Muck soils fall under the Organic Order in the Canadian system of soil classification.[4] Muck soils are organic soils, with at minimum of 30% organic matter and a depth of at least 40 cm.[4]

United States

In the USDA soil taxonomy, sapric may be a subtype of a haplohemist or glacistel type, and may also be a diagnostic organic soil material where the fiber content is less than one-sixth of the volume.[1] Muck soils are defined by the USDA NRCS as sapric organic soils that are saturated more than 30 cumulative days in normal years or are artificially drained.[5] In other words, it is a soil made up primarily of humus from drained swampland.

Use and vegetation

Muck onions 8640
Onion fields near Elba, New York, part of Torrey Farms, showing black dirt and windbreaks.

Muck soil is used for growing specialty crops such as onions, carrots, celery, and potatoes.


Muck farming on drained swamps is an important part of agriculture in New York, Ohio, Illinois, Indiana, Michigan, Wisconsin, and Florida, where mostly vegetables are grown. The muckland of Torrey Farms of Elba, New York, which covers the counties of Orleans, Niagara, and Genesee, is thought to be the largest continuous section of muckland in the world.[6] American "muckers" often have roots from the Netherlands or Eastern Europe, where their ancestors practiced a similar type of farming. Holland Marsh, north of Toronto, Ontario, is the site of the Muck Crops Research Station, a part of the University of Guelph.


Muck farming is controversial, because the drainage of wetlands destroys wildlife habitats and results in a variety of environmental problems. It is unlikely that any more will be created in the United States, because of environmental regulations. It is prone to problems. As the soil is very light, windbreaks are necessary to protect these fields in dry weather. It also can catch fire and burn underground for months. Oxidation also removes a portion of the soil each year, so it becomes progressively shallower. Oxidation also discharges carbon dioxide. Some muck land has been reclaimed and restored as wetlands for wildlife preserves.


The word muck has much usage in the English language, referring in some cases to agricultural soil, and in others to dirt in general, and animal dung in particular. Origins are probably from Norse, Danish, and Proto-Germanic roots referring to cow dung.[7][8]

See also


  1. ^ a b Canarache, A.; Vintila, I.I.; Munteanu, I. (2006). Elsevier's Dictionary of Soil Science. Elsevier. p. 745. ISBN 9780080561318.
  2. ^ Field Indicators of Hydric Soils in the United States: A Guide for Identifying and Delineating Hydric Soils (version 8.1 ed.). Natural Resources Conservation Service. 2017. p. 38. Archived from the original on 2017-05-24.
  3. ^ IUSS Working Group WRB (2015). World Reference Base for Soil Resources 2014, update 2015 (PDF). International soil classification system for naming soils and creating legends for soil maps. World Soil Resources Reports No. 106. Rome: FAO. ISBN 978-92-5-108370-3. Archived (PDF) from the original on 2016-12-13.
  4. ^ a b Canada Soil Survey Committee, Subcommittee on soil classification (1978). "The Canadian system of soil classification". Can. Dep. Agric. Publ. 1646. Supply and Services Canada (Pb), Ottawa, Ontario. 83pp.
  5. ^ Field Book for Describing and Sampling Soils (version 3.0 ed.). Natural Resources Conservation Service. 2012. p. 2–43. Archived from the original on 2017-05-01.
  6. ^ "Archived copy". Archived from the original on 2009-04-17. Retrieved 2009-06-01.CS1 maint: Archived copy as title (link)
  7. ^ "Online Etymology Dictionary". Archived from the original on 11 July 2015. Retrieved 10 July 2015.
  8. ^ "Muck - Definition of muck by Merriam-Webster". Archived from the original on 11 July 2015. Retrieved 10 July 2015.

External links

Armenians in France

Armenians in France (Armenian: ֆրանսահայեր fransahayer; French: Arméniens de France) are French citizens of Armenian ancestry. The French Armenian community is, by far, the largest in the European Union and the third largest in the world.Although the first Armenians settled in France in the Middle Ages, like most of the Armenian diaspora, the Armenian community in France was established by survivors of the Armenian Genocide of 1915. Others came through the second half of the 20th century, fleeing political and economic instability in the Middle Eastern countries (Turkey, Lebanon, Syria, Egypt and Iran) and, more recently, from Armenia.


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.

In USA soil taxonomy, Histosols are subdivided into:

Folists - Histosols that are not saturated with water for long periods of time during the year.

Fibrists - Histosols that are primarily made up of only slightly decomposed organic materials, often called peat.

Hemists - Histosols that are primarily made up of moderately decomposed organic materials.

Saprists - Histosols that are primarily made up of highly decomposed organic materials, often called muck.


Peat (), also known as turf (), is an accumulation of partially decayed vegetation or organic matter. It is unique to natural areas called peatlands, bogs, mires, moors, or muskegs. The peatland ecosystem is the most efficient carbon sink on the planet, because peatland plants capture CO2 naturally released from the peat, maintaining an equilibrium. In natural peatlands, the "annual rate of biomass production is greater than the rate of decomposition", but it takes "thousands of years for peatlands to develop the deposits of 1.5 to 2.3 m [4.9 to 7.5 ft], which is the average depth of the boreal [northern] peatlands". Sphagnum moss, also called peat moss, is one of the most common components in peat, although many other plants can contribute. The biological features of Sphagnum mosses act to create a habitat aiding peat formation, a phenomenon termed 'habitat manipulation'. Soils consisting primarily of peat are known as histosols. Peat forms in wetland conditions, where flooding or stagnant water obstructs the flow of oxygen from the atmosphere, slowing the rate of decomposition.Peatlands, particularly bogs, are the primary source of peat,

although less-common wetlands including fens, pocosins, and peat swamp forests also deposit peat. Landscapes covered in peat are home to specific kinds of plants including Sphagnum moss, ericaceous shrubs, and sedges (see bog for more information on this aspect of peat). Because organic matter accumulates over thousands of years, peat deposits provide records of past vegetation and climate by preserving plant remains, such as pollen. This allows the reconstruction of past environments and study changes in land use.Peat is harvested as an important source of fuel in certain parts of the world. By volume, there are about 4 trillion cubic metres (5.2 trillion cubic yards) of peat in the world, covering a total of around 2% of the global land area (about 3 million square kilometres or 1.2 million square miles), containing about 8 billion terajoules of energy. Over time, the formation of peat is often the first step in the geological formation of other fossil fuels such as coal, particularly low-grade coal such as lignite.Depending on the agency, peat is not generally regarded as a renewable source of energy, due to its extraction rate in industrialized countries far exceeding its slow regrowth rate of 1 mm per year, and as it is also reported that peat regrowth takes place only in 30-40% of peatlands. Because of this, the UNFCCC, and another organization affiliated with the United Nations classified peat as a fossil fuel. However, the Intergovernmental Panel on Climate Change (IPCC) has begun to classify peat as a "slowly renewable" fuel. This is also the classification used by many in the peat industry. At 106 g CO2/MJ, the carbon dioxide emission intensity of peat is higher than that of coal (at 94.6 g CO2/MJ) and natural gas (at 56.1) (IPCC).

Polish Soil Classification

The Polish Soil Classification (Polish: Systematyka gleb Polski) is a soil classification system used to describe, classify and organize the knowledge about soils in Poland.


Quicksand is a colloid hydrogel consisting of fine granular material (such as sand, silt or clay), and water.

Quicksand forms in saturated loose sand when the sand is suddenly agitated. When water in the sand cannot escape, it creates a liquefied soil that loses strength and cannot support weight. Quicksand can form in standing water or in upwards flowing water (as from an artesian spring). In the case of upwards flowing water, forces oppose the force of gravity and suspend the soil particles.

The saturated sediment may appear quite solid until a sudden change in pressure or shock initiates liquefaction. This causes the sand to form a suspension and lose strength. The cushioning of water gives quicksand, and other liquefied sediments, a spongy, fluid-like texture. Objects in liquefied sand sink to the level at which the weight of the object is equal to the weight of the displaced soil/water mix and the submerged object floats due to its buoyancy.

Liquefaction is a special case of quicksand. In this case, sudden earthquake forces immediately increase the pore pressure of shallow groundwater. The saturated liquefied soil loses strength, causing buildings or other objects on that surface to sink.

Whakaki Lagoon

Whakakī lagoon is a small coastal lagoon found on the east coast of New Zealands North island and is a part of the Hawke’s Bay region. The shoreline and sediment bed are mainly composed of sapric soil from nearby farming runoff and lithic sand from the sand bank of the neighboring Whakakī beach.

Classification systems

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