Rationalizing Mottling and Gleying in the Characterization and Classification of Canadian Soils

Mottling and gleying remain important characteristics for the classification of soils in Canada. The development of criteria for the morphological description of these soil redoximorphic features, of soil horizon nomenclature, the taxonomy of gleysolic and gleyed soils, as well as soil drainage classification began in the mid-1940s and continued for the next four decades. Despite advancements elsewhere globally, notably with Soil Taxonomy and the World Reference Base, there have been minimal refinements made in Canada, during the past quarter century. Various issues are identified, including the need for more succinct and clearer definitions, revisions of standards for the field characterization of redoximorphic features, more consistency in the application of concepts across existing taxa and systems, as well as a framework, perhaps a new ‘Redoximorphic Phase’, which would allow for the expression of dimensions of redoximorphic features not currently considered. Ultimately, it is recommended that a special committee be established to conduct a thorough study and present recommendations.