Soils that have weak B horizon
Soils derived from organic deposit that have an organic soil material thickness of more than 50 cm within 100 cm of the soil profile; occur in swampy area (unless artificially drained) or unsaturated highland. Also known as organic or peat soil.
Mineral soils that have spodic horizon (high in Fe, Al oxides and humus accumulation) within 2 meters of the soil surface; normally underlying an albic horizon.
Soils that have andic soil properties in 60 percent or more of the soil thickness within 60 cm of the mineral soil surface; formed from mostly volcanic ejecta dominated by allophane or Al-humic complexes with low bulk density.
Soils that have an oxic horizon within 150cm; or 40 percent or more clay within 18 cm and a kandic horizon with upper boundary within 100 cm of soil surface.
Soils that have high in shrinking and swelling clays; slickenslides or wedge-shaped peds with more than 30 percent clay to the depth of 50 cm or densic, lithic or paralithic contact if shallower and deep cracks (called gilgai) that open and close periodically.
Soils that have an argillic or kandic horizon with base saturation of less than 35 percent at 1.8 metres depth or at 75 cm below the fragipan.
Soils that have a mollic epipedon and high base saturation (more than 50 percent) throughout the soil to at least 180 cm or to a lithic or paralithic contact, whichever is shallower.
Other soils with no diagnostic horizons.
Convenient groupings of soils which characteristically occur over distinct landscape units and have very low agricultural potential.