pedality

Following the ideas of the Soil Survey Manual (Soil Survey Staff, 1951), Bullock et al. (1985) recommended to describe the grade of pedality as part of the description of microstructure. Bullock et al. (1985) and FitzPatrick (1984) based for micromorphological descriptions their grading on the only criterion visible in thin sections, namely the degree to which the aggregates are surrounded by voids. Systematic comparision of micromorphological and field descriptions revealed serious discrepancies in many cases. Specially soils with a high score for pedality in the field were not evaluated as such in thin sections (Langohr, personal communication), as pedality is not only a factor of separation.