Orders
- Alfisols — moderately weathered, form under boreal or broadleaf forests, rich in iron and aluminum
- Andisols — form in volcanic ash and defined as containing high proportions of glass and amorphous colloidal materials, including allophane, imogolite and ferrihydrite
- Aridisols — (from the Latin aridus, for “dry”) form in an arid or semiarid climate
- Entisols — do not show any "significant" soil profile development. Minimal soil horizons.
- Gelisols — soils of very cold climates which are defined as containing permafrost within two meters of the soil surface
- Histosols — consist primarily of organic materials
- Inceptisols — form quickly through alteration of parent material
- Mollisols — form in semiarid to semihumid areas, typically under a grassland cover
- Oxisols — best known for their occurrence in tropical rain forest
- Spodosols — typical soils of coniferous or boreal forests
- Ultisols — commonly known as red clay soils
- Vertisols — high content of expansive clay
Read more about this topic: USDA Soil Taxonomy
Famous quotes containing the word orders:
“Really, if the lower orders don’t set us a good example, what on earth is the use of them? They seem, as a class, to have absolutely no sense of moral responsibility.”
—Oscar Wilde (1854–1900)
“No man has received from nature the right to give orders to others. Freedom is a gift from heaven, and every individual of the same species has the right to enjoy it as soon as he is in enjoyment of his reason.”
—Denis Diderot (1713–1784)
“There are nine orders of angels, to wit, angels, archangels, virtues, powers, principalities, dominations, thrones, cherubim, and seraphim.”
—Gregory the Great, Pope (c. 540–604)