FAwR (version 1.1.2)

sweetgum: Lenhart's sweetgum (Liquidambar styraciflua L.) tree measurement data.

Description

The original data, also supplied in the package, are measures of stem diameter and height at various locations on the bole of 39 sweetgum trees from Texas, USA.

Usage

data(sweetgum)

Format

A data frame with 39 tree-level observations on the following 8 variables.

plot

Identifies the plot in which the tree was felled.

tree

A factor that identifies the tree.

dbh.in

The tree diameter (in.) at 1.37 m (4'6'')

stump.ht.ft

The height of the stump after felling (ft).

height.ft

The height of the tree (ft).

height.m

The height of the tree (m).

dbh.cm

The tree diameter (cm.) at 1.37 m (4'6'')

vol.m3

The estimated biological volume of the stem (cubic meters).

Details

The height measure is of the standing tree, so it includes the stump height. The volume was computed by fitting a spline to the height and diameter measures, and integrating the solid that corresponds to the profile of the spline. See Section 2.4.2 of Robinson and Hamann (2010) for more details.

References

Robinson, A.P., and J.D. Hamann. 2010. Forest Analytics with R: an Introduction. Springer.

Examples

# NOT RUN {
data(sweetgum)
str(sweetgum)
# }