gtree: Function to compute basal area of a tree

In biometrics: A Package for Biometrics and Modelling

Function to compute basal area of a tree

Description

The function computes the basal area of a tree (g), which only depends on its diameter at breast-height (d). The basal area of a tree is computed as

g = \left(\frac{\pi}{k}\right) d^{2}

where the constant k depends on whether the diameter and the resulting basal area are in the units of the metric or imperial system.

Usage

gtree(x, metric = TRUE)

Arguments

x	is the object (i.e., vector or scalar) having tree diameter. By default the function assumes that the unit of measurement of this variable is cm.
metric	is a logic value, the default is to TRUE, thus the diameter has to be expressed in cm, and the resulting basal area will be expressed in m^{2}. If metric is FALSE, the diameter has to be in inches and the resulting basal area will be in ft^{2}.

Value

The value of basal area in m^{2} or in ft^{2}, depending on the units of measurement being defined.

Author(s)

Christian Salas-Eljatib

Examples

#Using the function
 gtree(40)
 gtree(x=30)
gtree(x=11.81,metric=FALSE)

biometrics documentation built on March 20, 2026, 5:09 p.m.