Calculate crown base height from DBH and total height

Calculates the height at which the live crown begins. Two methods available:

Usage

calc_crown_base_height(
  dbh,
  height,
  species,
  allometric_params = get_default_allometric_params()
)

Arguments

dbh

Numeric vector. Tree diameter at breast height (cm)

height

Numeric vector. Total tree height (m)

species

Character vector. Species codes

allometric_params

List. Allometric parameters (from get_default_allometric_params)

Value

Numeric vector. Crown base height (m)

Details

**Reese quadratic method** (default, more realistic): CBH = b0 + b1*H + b2*D + b3*H^2 + b4*D^2 + b5*(H*D)

**Simple ratio method**: crown_ratio = a - b * log(DBH) crown_base_height = height * (1 - crown_ratio)

Method is determined by allometric_params$cbh_method.

References

Reese et al. Species-specific crown base height equations for pinyon-juniper woodlands (PIED, JUMO, JUOS).

Examples

dbh <- c(10, 20, 30)
height <- calc_height(dbh, c("PIED", "PIED", "PIED"))

# Using Reese quadratic equations (default)
calc_crown_base_height(dbh, height, c("PIED", "PIED", "PIED"))
#> [1] 1.300000 1.300000 1.388753

# Using simple ratio method
params <- get_default_allometric_params(use_reese_cbh = FALSE)
calc_crown_base_height(dbh, height, c("PIED", "PIED", "PIED"), params)
#> [1] 2.582661 4.375771 5.666247