datana (version 1.0.6)

hgrdfir: Tree height growth of Douglas-fir sample trees in the Northwest of the United States

Description

Data contains 148 observations on the height growth of dominant trees of Pseudotsguga mensiezzi in the Northwest of the United States.

Usage

data(hgrdfir)

Format

The data frame contains seven variables as follows:

natfor.id

Code identifier.

plot.code

Plot number identification

tree.code

Tree number identification.

dbh

Diameter at breast height at sampling, in in.

toth

Total height at sa,pling, in ft.

age

Age of tree, yr.

height

Height at a given age, in ft.

References

- Monserud RA. 1984. Height growth and site index curves for Inland Douglas-fir based on stem analysis data and forest habitat type. Forest Science 30(4):943-965.

- Salas C, Stage AR, and Robinson AP. 2008. Modeling effects of overstory density and competing vegetation on tree height growth. Forest Science 54(1):107-122. tools:::Rd_expr_doi("10.1093/forestscience/54.1.107")

Examples

data(hgrdfir)    
head(hgrdfir)
unique(hgrdfir$tree.code)
table(hgrdfir$plot.code,hgrdfir$tree.code)
tapply(hgrdfir$dbh, hgrdfir$tree.code, mean)
tapply(hgrdfir$dbh, hgrdfir$tree.code, mean) #dbh of each sample tree
tapply(hgrdfir$toth, hgrdfir$tree.code, mean) #toth of each sample tree