plants2: Sapling counts from sample plots of sapling stands in...

plants2R Documentation

Sapling counts from sample plots of sapling stands in Finland.

Description

Independent Norway Spruce regeneration establishment data.

Usage

data(plants2)

Format

A data frame with 123 observations on the following 8 variables.

planted

The number of planted spruce saplings on the plot

pines

The number of natural pine saplings

spruces

The number of natural spruce saplings

birches

The number natural birch saplings

othersp

The number of natural saplings of other species

hcrop

The mean height of crop species

hdecid

The mean height of deciduous tree species

sitetype

Site fertility class (small number indicates more fertile site)

Details

The data are collected from 123 fixed-area sample plots with similar age of planted spruce saplings. The number of saplings per species and the height of crop species (spruce and pine) and competing vegetation (birch and other broadleaved trees) has been recorded for all plots. The data includes one plot per forest stand.

References

Miina, J. and Saksa, T. 2006. Predicting regeneration establishment in Norway spruce plantations using a multivariate multilevel model. New Forests 32: 265-283. doi: 10.1007/s11056-006-9002-y

Mehtatalo, Lauri and Lappi, Juha 2020. Biometry for Forestry and Environmental Data: with examples in R. New York: Chapman and Hall/CRC. 426 p. doi: 10.1201/9780429173462

Examples

data(plants2)

glm1 <- glm(spruces ~ hdecid, family=quasipoisson(), data=plants2)

lmfor documentation built on April 30, 2022, 1:08 a.m.