NZSC Soil Orders:
Allophanic Soils [L]
Allophanic Soils are dominated by allophane (also imogolite or ferrihydrite) minerals.
Allophanic Soils have a large affinity for phosphate. Up to 30 tonnes/ha of phosphorous may be locked away in intensively farmed topsoils.
Anthropic Soils [A]
Anthropic Soils are constructed by, or drastically disturbed, by people.
New Zealands largest single areas of Anthropic Soils were formed by gold dredging in Central Otago and Westland.
Brown Soils [B]
Brown Soils have a brown or yellow-brown subsoil below a dark grey-brown topsoil.
Our most extensive soils, covering 43% of New Zealand.
Gley Soils [G]
Gley Soils, together with Organic Soils, represent the original extent of New Zealand wetlands.
Gley Soils are strongly affected by waterlogging and have been chemically reduced. They have light grey subsoils, usually with reddish brown or brown mottles.
Granular Soils [N]
Granular Soils are clayey soils formed from material derived by strong weathering of volcanic rocks or ash.
These highly productive soils have been used continuously for horticulture for up to 40 years at Pukekohe, despite some erosion.
Melanic Soils [E]
Melanic Soils have black or dark grey well structured topsoils.
Perhaps the most naturally fertile soils in New Zealand. They grow high quality pinot noir.
Organic Soils [O]
Organic Soils are formed in the partly decomposed remains of wetland plants (peat) or forest litter.
Serving as giant sponges in the landscape, these soils can hold up to 20 times their weight in water.
Oxidic Soils [X]
Oxidic Soils are clayey soils that have formed as a result of weathering over extensive periods of time in volcanic ash or dark volcanic rock.
The first grape vines in New Zealand were probably planted on these soils by an associate of Samuel Marsden at Kerikeri in 1817.
Pallic Soils [P]
Pallic Soils have pale coloured subsoils, due to low contents of iron oxides.
A cubic metre of some subsoils can weigh more than 1.8 tonnes.
Podzols are strongly acid soils that usually have a bleached horizon immediately beneath the topsoil.
The impressive contrast in horizons displays the potent effect that particular tree species, for example Kauri, can have on soil formation.
Pumice Soils [M]
Pumice Soils are sandy or gravelly soils dominated by pumice, or pumice sand with a high content of natural glass.
Mostly derived from one of the greatest volcanic eruptions ever known from the crater now occupied by Lake Taupo.
Raw Soils [W]
Raw Soils are very young soils. They lack distinct topsoil development or are fluid at a shallow depth.
Infant soils that may never grow older because of active erosion or sedimentation.
Recent Soils [R]
Recent Soils are weakly developed, showing limited signs of soil-forming processes.
The highest recorded carrot production in the world was from a Recent Soil on the Taieri Plain.
Semiarid Soils [S]
Semiarid Soils are dry for most of the growing season. Rain is not sufficient to leach through the soil, so lime and salts accumulate in the lower subsoil.
Great soils for rabbits with densities of more than 800 rabbits per square kilometre during plagues.