Composition of a Conover‐Brookston Map Unit in Southeastern Michigan

Abstract

AbstractA Conover‐Brookston soil mapping unit, named on the basis of point‐transect observations after its delineation, was reevaluated through laboratory characterization of the major components of this map unit. Eight Conover (fine‐loamy, mixed, mesic Udollic Ochraqualf) and eight Brookston (fine‐loamy, mixed, mesic Typic Argiaquoll) pedons, identified by the transect observations, were investigated by laboratory determinations.The particle‐size distributions indicated some translocation of clay from the surface to the subsoil in each series. However, even in those pedons with other characteristics of an argillic horizon, the ratios of fine‐clay in total clay of B2/Ap horizons were insufficient for an argillic horizon as defined in Soil Taxonomy. Alternative criteria are proposed.The 16 pedons covered the whole particle‐size range of the fineloamy family. The transects of the map unit after its delineation overestimated its homogeneity, judged by the laboratory analyses.