soiltreat {datana}

Soil treatments on the height growth of 2-year-old seedlings.

Description

Treatments were assigned at random to the three plots within each of 11 blocks. Each plot was made up of 50 seedlings. Average 5-year height increment was the criterion for evaluating treatments. Initial heights and 5-year increments are part of the data.

Usage

data(soiltreat)

Format

Contains the following columns:

block

Code for the corresponding block used in the experiment.

treat

Treatment level.

ini.h

Initial height of the plot, in m.

inc.h

5-yr increment in height of the plot, in m.

Source

The data come from page 71 of Freese (1967), and were typed by Nayeli Ramirez, a student of Prof Christian Salas-Eljatib.

References

Freese F. 1967. Elementary statistical methods for foresters. Agriculture Handbook 317, U.S. Department of Agriculture, Forest Service, Washington DC, USA. 87p.

Examples

data(soiltreat)    
tapply(soiltreat$inc.h,soiltreat$treat,summary)