Mulmic qualifier (submitted by John Hollis, Allan Lilly and Bob Jones, UK)

[StephanMantelISRIC]

The addition of Mulmic material is useful in that It recognises the presence of soils that had organic upper horizons before effective drainage was installed. However, the structural requirements exclude a number of topsoils that would qualify on the organic carbon criteria but not on the structural criteria, some because they have irreversibly dried out forming hard, coarse blocky peds or dense apedal layers, a state locally known as ‘Drummy peat’. In addition many podzols or upland Cambisols under semi-natural vegetation have mor horizons that would qualify on the organic criteria but have platy or apedal structure. This means that, at present, there is no means of recognising the organic-rich nature of their mor horizons. We therefore think that there is a need to expand the definition of Mulmic to include the structural conditions of ‘drummy peat’ and also to add another qualifier that would recognise the presence of thin, organic-rich mor horizons with platy or no structure.

(submitted by John Hollis, Allan Lilly and Bob Jones, UK)