- Day, Maurice W.
Department of Forestry, Michigan State University
In 1940, a series of thinning plots was established in a 30-year-old spruce-fir stand in the Dunbar Forest, near Sault Ste. Marie, Michigan. Later, additional plots were added and periodically thinned and measured. Earlier reports (1,2) describe preliminary results of this work; this report will the record for this study.
The study area is a natural even-aged stand of white spruce, black spruce, and balsam fir. This stand was established following a fire about 1908 to 1910. Stand composition varies somewhat, but white spruce makes up about one-half the stand, followed by balsam fir and black spruce. Only scattered stems of aspen and paper birch are present. Thus, this stand is atypical since most spruce-fir stands in this region have a larger component of aspen and paper birch. The stand is located on an upland site with a Keeweenaw stony, loamy sand soil. The average site index for white spruce is about 50.