Download and crop data from the NRCS SSURGO soils database.

Source: R/SSURGO_FUNCTIONS.R

This is an efficient method for spatially merging several different soil survey areas as well as merging their tabular data.

get_ssurgo(
  template,
  label,
  raw.dir = paste0(tempdir(), "/FedData/raw/ssurgo"),
  extraction.dir = paste0(tempdir(), "/FedData/"),
  force.redo = FALSE
)

Arguments

template

An Simple Feature or SpatRaster object to serve as a template for cropping. Optionally, a vector of area names, e.g., c('IN087','IN088') may be provided.

label

A character string naming the study area.

raw.dir

A character string indicating where raw downloaded files should be put. The directory will be created if missing. Defaults to './RAW/SSURGO/'.

extraction.dir

A character string indicating where the extracted and cropped SSURGO shapefiles should be put. The directory will be created if missing. Defaults to './EXTRACTIONS/SSURGO/'.

force.redo

If an extraction for this template and label already exists, should a new one be created? Defaults to FALSE.

Value

A named list containing the 'spatial' and 'tabular' data.

Details

get_ssurgo returns a named list of length 2:

  1. 'spatial': A Simple Feature of soil mapunits in the template, and

  2. 'tabular': A named list of data.frames with the SSURGO tabular data.

Examples

if (FALSE) {
# Get the NRCS SSURGO data (USA ONLY)
SSURGO.MEVE <- get_ssurgo(template = FedData::meve, label = "meve")

# Plot the VEP polygon
plot(meve$geometry)

# Plot the SSURGO mapunit polygons
plot(SSURGO.MEVE$spatial, lwd = 0.1, add = T)

# Or, download by Soil Survey Area names
SSURGO.areas <- get_ssurgo(template = c("CO670", "CO075"), label = "CO_TEST")

# Let's just look at spatial data for CO675
SSURGO.areas.CO675 <- SSURGO.areas$spatial[SSURGO.areas$spatial$AREASYMBOL == "CO075", ]

# And get the NED data under them for pretty plotting
NED.CO675 <- get_ned(template = SSURGO.areas.CO675, label = "SSURGO_CO675")

# Plot the SSURGO mapunit polygons, but only for CO675
plot(NED.CO675)
plot(SSURGO.areas.CO675, lwd = 0.1, add = T)
}