Acknowledgements

Many have contributed to the development of this version, but in particular the guidance and encouragement of Ben Clayden is gratefully acknowledged. Alastair Wilson advanced the work considerably by developing the hierarchies of the Oxidic and Granular Soils orders, the Mafic Brown Soils subgroups and revising the Ultic Soils hierarchy. The Allophanic Soils and Pumice Soils proposals are adapted from the ICOMAND proposal (Parfitt and Clayden 1991) and Roger Parfitt’s assistance with these, and other orders, has been appreciated. There are many others who have willingly supplied information, discussed concepts and helped define classes. In particular I thank Trevor Webb, Robin Palmer, Brian Purdie, Hugh Wilde, Iain Campbell, Geoff Mew, Mike Laffan, Peter McIntosh, Alan Palmer, Jim Pollok, David Lowe, Megan Balks, Bob Allbrook, Malcolm McLeod, Gary Orbell and Peter Singleton. Cyril Childs’ editorial help was also much appreciated.

Parfitt RL, Clayden B 1991. Andisols - the development of a new order in Soil Taxonomy. Geoderma [Internet]. 49(3):181–198. https://doi.org/10.1016/0016-7061(91)90075-5