Soil Taxonomy

  1. Anthropic epipedon
    Mineral soil material that shows some evidence of disturbance by human activity (mixing of the upper 18cm)
  2. Folistic Epipedon
    A layer that is saturated for less than 30 days in normal years and is 20cm or more thick or is an Ap horizon
  3. Histic Epipedon
    A layer that is characterized by saturation for more than 30 days and reduction for some time during normal years
  4. Mollic Epipedon
    Color value of 4 or 5
  5. Ochric Epipedon
    Fails to meat definitions for the other seven epipedons
  6. Umbric Epipedon
    dominant colors with a value of 3 or less
  7. Agric Horizon
    illuvial horizon that has formed under cultivation and contains significant amounts of illuvial silt, clay, and humus. Directly below the Ap horizon
  8. Argillic Horizon
    Subsurface horizon with higher percentage of clay than the overlying horizon. May be exposed by erosion.
  9. Calcic Horizon
    An illuvial horizon in which secondary calcium carbonates have accumulated15% or more CaCO3 equivalent.
  10. Cambic Horizon
    Result of physicalalterations, chemical transformations, or removals. 15 cm thick or more.
  11. Duripan
    Silica cemented subsurface horizon
  12. Fragipan
    15cm thick, evidence of pedogenesis, coarse structure, not effervescent.
  13. Glossic Horizon
    result of degradation of an argillic, kandic, or natric horizon from which clay and free iron oxides are removed.
  14. Gypsic
    Gypsum has accumulated or been transformed
  15. Kandic Horizon
    vertically continuous subsurface horizon that underlies a coarser textured surface horizon.
  16. Natric horizon
    illuvial horizon that is normally present in the subsurface and has a significantly higher percentage of silicate clay than the overlying horizons. Evidence of clay illuviation accelerated by sodium
  17. Oxic Horison
    Subsurface horizon that does not have andic properies and is 30 cm thick or more.
  18. Spodic Horizon
    illuvial layer with 85% more spodic materials. Subsurface horizon
  19. Soil Moisture regimes
    Aquic (saturated with water), Aridic and Torric (arid climates) Udic (not dry in any part for as long as 90 cumulative days, soil temp is lower than 22C; humid climates) Ustic (intermediat bn aridic and udic; moisture is limited but present; tropical and subtropical) Xeric (Mediterranean dry in all parts for 45 or more days
  20. Soil Termperature Regimes
    Gelic (Annual soil temp at or below 0C) Cryic (0-8C) Frigid(soil warmer than cryic in summer) Mesic (8-15C) Thermic (15-22) Hyperthermic (22+)
Card Set
Soil Taxonomy
Soil Taxonomy