Coarse Woody Debris and Regeneration of
Eastern Hemlock in Northern Michigan



Russell L. Corinth
School of Science and Natural Resources
Lake Superior State University
Sault Ste. Marie, Michigan 49783 USA


		Abstract.    In the Lake States, hemlock is most productive growing on cool
moist sites developed from glacial or fluvial remains. Common seedbeds for hemlock
range from mineral soils and well decomposed litter to decayed wood and moss mats. The
purpose of this study was to evaluate coarse woody debris (CWD) as a regeneration site
for eastern hemlock seedlings in the Eastern Upper Peninsula of Michigan. Fifty-eight
plots were sampled within a 3.4 ha hemlock stand having characteristics indicative of an
old growth forest. Seedlings were tallied as to their germinating substrate - soil or coarse
woody debris. The coarse woody debris at each plot was measured for its stage of decay
and surface area. ANOVA/Tukey test results revealed significantly greater amounts of
regeneration occurring on logs in the later stages of deterioration (a=0.05). Notably less
regeneration was found on logs in the initial stages of decay and the soil.  A positive trend
was also noted between seedling numbers and coarse woody debris diameter. It was
concluded that although only accounting for a small fraction of the forest floor, large logs
as a component of coarse woody debris play an important role in successful seedling
recruitment by providing a protected site with favorable physical and nutrient properties.




Selected References


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Maser, C., R.F. Tarrant, J.M. Trappe, and J.F. Franklin, tech. eds. 1988. From the
forest to the sea: a story of fallen trees. USDA Forest Service Gen. Tech. Rep.
PNW-GTR-229





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