| New Soil Order classification | ORGANIC
Occur in wetland sites, as peat or forest litter. |
| Old Soil Group classification | Organic | |
| Common names associated with this Soil Order | Rotoatara, Poukawa, Pongakawa, Farndon, Turamoe. |
| Physical characteristics | - Very rare for farm forestry to occur on these sites - 'needs' are amenity trees, wetland development or protection, possibly shelterbelt.
- Special landscape site, often drained, originally wetland environment.
- Very low bulk density, but has low bearing strength, therefore roads need foundation design.
- High shrinkage potential when dry.
- Low pH, acidic.
- Low natural soil nutrient status with potential deficiencies in potassium, nitrogen, sulphur, and phosphate, and trace elements selenium, copper, and molybdenum. Respond well to lime.
- Natural fertility is related to hydrology eg. higher fertility. Organic soils are reliant on groundwater bringing in nutrients from surrounding mineral soils.
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| Drainage and moisture availability | - Very poorly drained with low aeration.
- Plant-available water ranges from moderate to high.
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| Rooting depth | - Excellent. Soils are consistently deeper than 60cm. Allows trees to tap the nutrient reserves and moisture zones.
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Rotoatara soil
Source: Dan Bloomer