The von Post scale replaces the soil textural triangle as a baseline for description of highly organic soils, and was shown to relate ‘humification’ to other measurements of soil functionality. In the research areas, desirable plants (forage grasses) grew most strongly in areas with von Post scores between 7 and 9. It may also indicate topographical or hydrological conditions that support or impair land restoration. It showed strong statistical relationships with soil depth, colour, K, pH, ash, hydrology, and smell, emphasizing its predictive value as a multi-variate indicator for field analysis.

Although Sphagnum when left to itself passes from fibre to colloidal paste with no intermediate crumb stage, the von Post score correlates strongly with other characteristics of good soil functionality.

This elegantly simple test clearly describes the continuum found in the research areas, from a sponge-like catotelm with nearly unlimited hydraulic conductivity to impermeable black peat. Some experience is needed to use the method, as the actual instructions appear to exist only in Old Swedish bowdlerised versions with the hard words left out were found on the Web.

Colour and viscosity of exudate, proportion and condition of remaining fibre and other qualities are noted a score is assigned according to the table above. The von Post scale is simple to use: a handful of wet soil (small enough to cover with the fingers of one hand) is squeezed very hard, until as much as possible has extruded through the fingers.

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