Display modeled tree crowns projected vertically on subplot boundaries

plot_crowns() draws vertically projected tree crowns as discs overlaid on FIA subplot or microplot boundaries. The full four-subplot cluster, or individual subplots, can be displayed with trees >= 5.0 in. (12.7 cm) diameter. Individual microplots can also be displayed with saplings (i.e., trees < 5 in. diameter).

Usage

plot_crowns(
  tree_list,
  subplot = NULL,
  microplot = FALSE,
  linear_unit = "ft",
  main = "",
  crown_col = "#328e13",
  stem_col = "#b85e00",
  subp_border_lwd = 3,
  subp_border_col = "gray61"
)

Arguments

tree_list

A data frame with tree records for one FIA plot. Must have columns SUBP (FIA subplot number), STATUSCD (FIA integer tree status, 1 = live), DIA (tree diameter), HT (tree height), ACTUALHT (tree actual height, ACTUALHT < HT indicating a broken top), DIST (stem distance from subplot/microplot center), AZIMUTH (horizontal angle from subplot/microplot center to the stem location, in range 0:359), and CRWIDTH (tree crown width).

subplot

Optional integer subplot number in the range 1:4 indicating a specific subplot for display. May be NULL or NA to display the whole four-point cluster plot.

microplot

A logical value, TRUE to display the modeled crowns of saplings overlaid of the microplot boundary of subplot = n. The default is FALSE. Ignored if subplot is not specified.

linear_unit

An optional character string specifying the linear distance unit. Defaults to the native FIA unit of "ft", but may be set to "m" instead (or "meter" / "metre"), in which case subplot boundaries will be display in meters, tree heights and crown widths are assumed to be given in meters, and tree diameters are assumed to be given in centimeters. TODO: not currently implemented

main

Character string giving the main plot title (on top).

crown_col

The color of tree crowns, e.g., either a color name (as listed by colors()) or a hexadecimal string.

stem_col

The color of tree stems when plotting an individual subplot or microplot (see crown_col above).

subp_border_lwd

The line width of subplot boundaries. Must a positive number.

subp_border_col

The color of subplot boundaries (see crown_col above).

Value

The input, invisibly.

See also

calc_crwidth(), calc_crown_overlay()

Examples

trees <- within(plantation, CRWIDTH <- calc_crwidth(plantation))

plot_crowns(trees, main = "plantation plot")


plot_crowns(trees, subplot = 4, main = "plantation subplot 4")


plot_crowns(trees, subplot = 4, microplot = TRUE,
            main = "plantation microplot 4")