Spodosol EU
A representative soil profile of a Spodosol with a plaggen epipedon. Spososols are a soil order in USDA Soil Taxonomy. The feature that is common to most Spodosols is the presence of a spodic horizon (buried Bs horizon), in which amorphous mixtures of organic matter and aluminum, with or without iron, have accumulated. The spodic horizon may be destroyed by cultivation, yet spodic materials may still be present.
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 are extensive in the southeastern part of the United States, the Northeast, the Great Lakes States, and the mountains of the West.
The plaggen epipedon is a human-made surface layer 50 cm or more thick that has been produced by a specific type of long-continued manuring. In Europe during medieval times, sod or other materials commonly were used for bedding livestock. Source materials for the bedding included heather, grass sod, or forest litter and turf (Blume and Leinweber, 2004). The bedding materials, mixed with manure, were subsequently spread on individual gardens as well as crop fields surrounding the village and spaded into the surface. The mineral materials brought in by this kind of manuring eventually produced an appreciably thickened Ap horizon (as much as 1 m or more thick) .
In northwestern Europe this custom was associated with the poorly fertile, sandy Spodosols. The practice more or less ceased at the turn of the 19th century, when fertilizers became available. Individual fields with a plaggen epipedon may be small (<1 to a few hectares), but some are much larger. Extensive areas of sandy soils in northwestern Europe were influenced with plaggen management techniques, and plaggen epipedons are estimated to collectively cover a few thousand km2, commonly clustered in areas around the villages (Blume and Leinweber, 2004).
Contributed by Craig Ditzler, USDA-NRCS, ret.
For additional information about soil classification, visit:
www.nrcs.usda.gov/wps/portal/nrcs/main/soils/survey/class...
Spodosol EU
A representative soil profile of a Spodosol with a plaggen epipedon. Spososols are a soil order in USDA Soil Taxonomy. The feature that is common to most Spodosols is the presence of a spodic horizon (buried Bs horizon), in which amorphous mixtures of organic matter and aluminum, with or without iron, have accumulated. The spodic horizon may be destroyed by cultivation, yet spodic materials may still be present.
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 are extensive in the southeastern part of the United States, the Northeast, the Great Lakes States, and the mountains of the West.
The plaggen epipedon is a human-made surface layer 50 cm or more thick that has been produced by a specific type of long-continued manuring. In Europe during medieval times, sod or other materials commonly were used for bedding livestock. Source materials for the bedding included heather, grass sod, or forest litter and turf (Blume and Leinweber, 2004). The bedding materials, mixed with manure, were subsequently spread on individual gardens as well as crop fields surrounding the village and spaded into the surface. The mineral materials brought in by this kind of manuring eventually produced an appreciably thickened Ap horizon (as much as 1 m or more thick) .
In northwestern Europe this custom was associated with the poorly fertile, sandy Spodosols. The practice more or less ceased at the turn of the 19th century, when fertilizers became available. Individual fields with a plaggen epipedon may be small (<1 to a few hectares), but some are much larger. Extensive areas of sandy soils in northwestern Europe were influenced with plaggen management techniques, and plaggen epipedons are estimated to collectively cover a few thousand km2, commonly clustered in areas around the villages (Blume and Leinweber, 2004).
Contributed by Craig Ditzler, USDA-NRCS, ret.
For additional information about soil classification, visit:
www.nrcs.usda.gov/wps/portal/nrcs/main/soils/survey/class...