% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/diagnostics-horizons-usda.R
\name{oxic_usda}
\alias{oxic_usda}
\title{Oxic horizon (USDA Soil Taxonomy)}
\usage{
oxic_usda(pedon, ...)
}
\arguments{
\item{pedon}{A \code{\link{PedonRecord}}.}

\item{...}{Passed to \code{\link{ferralic}}.}
}
\value{
A \code{\link{DiagnosticResult}} (with \code{name = "oxic_usda"}).
}
\description{
The USDA oxic horizon is the diagnostic of Oxisols. Its central
criteria match the WRB 2022 ferralic horizon closely enough that
v0.2 simply delegates: every fixture that classifies as Oxisol via
USDA also classifies as Ferralsol via WRB and vice-versa. The
fine-grained differences (USDA's water-dispersible-clay test, the
sand-fraction weatherable-mineral cut-offs) are tracked in the
diagnostics.yaml for v0.8 refinement.
}
\references{
Soil Survey Staff (2014). \emph{Keys to Soil Taxonomy},
  12th edition. USDA-NRCS, Washington DC. Chapter 3 -- Diagnostic
  Horizons; oxic.
}
