FLETCHER, TARA S.* AND JOHN L. VANKAT. Department of Botany, Miami University, Oxford, OH 45056. - Understory species as keys to defining old-growth forests of southcentral Alaska.
There is no universal definition for the term "old growth"
forest because old-growth properties are specific to location. Alaska
has two well-known forest types, the Coastal and Interior forests. A
third, poorly-studied type occurs in southcentral Alaska where
climatic conditions are unique. The canopies of young and old-growth
forests in this area are dominated by only two tree species, white
spruce (Picea glauca) and paper birch (Betula
papyrifera). However, understory species richness is much
greater. Therefore, shrubs and herbs may provide additional, if not
greater, insight into characterizing the old-growth forests. During
the summer of 1997, we conducted percent cover estimates on study
plots established on Fort Richardson Army Base near Anchorage to
determine whether some understory species uniquely characterize
old-growth forests of southcentral Alaska. The plots were located to
encompass various landforms and successional stages. Findings
indicate that understory communities are more influenced by tree
canopy cover than they are by topography or successional stage.
Although the presence or absence of understory species is consistent
across stands, species abundances are variable and aid in identifying
understory communities.
Key words: Alaska, old-growth forest, southcentral Alaska